Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * linux/kernel/sys.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | */ | |
6 | ||
9984de1a | 7 | #include <linux/export.h> |
1da177e4 LT |
8 | #include <linux/mm.h> |
9 | #include <linux/utsname.h> | |
10 | #include <linux/mman.h> | |
1da177e4 LT |
11 | #include <linux/reboot.h> |
12 | #include <linux/prctl.h> | |
1da177e4 LT |
13 | #include <linux/highuid.h> |
14 | #include <linux/fs.h> | |
74da1ff7 | 15 | #include <linux/kmod.h> |
cdd6c482 | 16 | #include <linux/perf_event.h> |
3e88c553 | 17 | #include <linux/resource.h> |
dc009d92 EB |
18 | #include <linux/kernel.h> |
19 | #include <linux/kexec.h> | |
1da177e4 | 20 | #include <linux/workqueue.h> |
c59ede7b | 21 | #include <linux/capability.h> |
1da177e4 LT |
22 | #include <linux/device.h> |
23 | #include <linux/key.h> | |
24 | #include <linux/times.h> | |
25 | #include <linux/posix-timers.h> | |
26 | #include <linux/security.h> | |
27 | #include <linux/dcookies.h> | |
28 | #include <linux/suspend.h> | |
29 | #include <linux/tty.h> | |
7ed20e1a | 30 | #include <linux/signal.h> |
9f46080c | 31 | #include <linux/cn_proc.h> |
3cfc348b | 32 | #include <linux/getcpu.h> |
6eaeeaba | 33 | #include <linux/task_io_accounting_ops.h> |
1d9d02fe | 34 | #include <linux/seccomp.h> |
4047727e | 35 | #include <linux/cpu.h> |
e28cbf22 | 36 | #include <linux/personality.h> |
e3d5a27d | 37 | #include <linux/ptrace.h> |
5ad4e53b | 38 | #include <linux/fs_struct.h> |
b32dfe37 CG |
39 | #include <linux/file.h> |
40 | #include <linux/mount.h> | |
5a0e3ad6 | 41 | #include <linux/gfp.h> |
40dc166c | 42 | #include <linux/syscore_ops.h> |
be27425d AK |
43 | #include <linux/version.h> |
44 | #include <linux/ctype.h> | |
6fa3eb70 S |
45 | #include <linux/mm.h> |
46 | #include <linux/mempolicy.h> | |
47 | #include <linux/sched.h> | |
1da177e4 LT |
48 | |
49 | #include <linux/compat.h> | |
50 | #include <linux/syscalls.h> | |
00d7c05a | 51 | #include <linux/kprobes.h> |
acce292c | 52 | #include <linux/user_namespace.h> |
7fe5e042 | 53 | #include <linux/binfmts.h> |
1da177e4 | 54 | |
4a22f166 SR |
55 | #include <linux/sched.h> |
56 | #include <linux/rcupdate.h> | |
57 | #include <linux/uidgid.h> | |
58 | #include <linux/cred.h> | |
59 | ||
04c6862c | 60 | #include <linux/kmsg_dump.h> |
be27425d AK |
61 | /* Move somewhere else to avoid recompiling? */ |
62 | #include <generated/utsrelease.h> | |
04c6862c | 63 | |
1da177e4 LT |
64 | #include <asm/uaccess.h> |
65 | #include <asm/io.h> | |
66 | #include <asm/unistd.h> | |
67 | ||
6fa3eb70 S |
68 | #ifdef CONFIG_MT_PRIO_TRACER |
69 | # include <linux/prio_tracer.h> | |
70 | #endif | |
71 | ||
1da177e4 LT |
72 | #ifndef SET_UNALIGN_CTL |
73 | # define SET_UNALIGN_CTL(a,b) (-EINVAL) | |
74 | #endif | |
75 | #ifndef GET_UNALIGN_CTL | |
76 | # define GET_UNALIGN_CTL(a,b) (-EINVAL) | |
77 | #endif | |
78 | #ifndef SET_FPEMU_CTL | |
79 | # define SET_FPEMU_CTL(a,b) (-EINVAL) | |
80 | #endif | |
81 | #ifndef GET_FPEMU_CTL | |
82 | # define GET_FPEMU_CTL(a,b) (-EINVAL) | |
83 | #endif | |
84 | #ifndef SET_FPEXC_CTL | |
85 | # define SET_FPEXC_CTL(a,b) (-EINVAL) | |
86 | #endif | |
87 | #ifndef GET_FPEXC_CTL | |
88 | # define GET_FPEXC_CTL(a,b) (-EINVAL) | |
89 | #endif | |
651d765d AB |
90 | #ifndef GET_ENDIAN |
91 | # define GET_ENDIAN(a,b) (-EINVAL) | |
92 | #endif | |
93 | #ifndef SET_ENDIAN | |
94 | # define SET_ENDIAN(a,b) (-EINVAL) | |
95 | #endif | |
8fb402bc EB |
96 | #ifndef GET_TSC_CTL |
97 | # define GET_TSC_CTL(a) (-EINVAL) | |
98 | #endif | |
99 | #ifndef SET_TSC_CTL | |
100 | # define SET_TSC_CTL(a) (-EINVAL) | |
101 | #endif | |
1da177e4 LT |
102 | |
103 | /* | |
104 | * this is where the system-wide overflow UID and GID are defined, for | |
105 | * architectures that now have 32-bit UID/GID but didn't in the past | |
106 | */ | |
107 | ||
108 | int overflowuid = DEFAULT_OVERFLOWUID; | |
109 | int overflowgid = DEFAULT_OVERFLOWGID; | |
110 | ||
1da177e4 LT |
111 | EXPORT_SYMBOL(overflowuid); |
112 | EXPORT_SYMBOL(overflowgid); | |
1da177e4 LT |
113 | |
114 | /* | |
115 | * the same as above, but for filesystems which can only store a 16-bit | |
116 | * UID and GID. as such, this is needed on all architectures | |
117 | */ | |
118 | ||
119 | int fs_overflowuid = DEFAULT_FS_OVERFLOWUID; | |
120 | int fs_overflowgid = DEFAULT_FS_OVERFLOWUID; | |
121 | ||
122 | EXPORT_SYMBOL(fs_overflowuid); | |
123 | EXPORT_SYMBOL(fs_overflowgid); | |
124 | ||
125 | /* | |
126 | * this indicates whether you can reboot with ctrl-alt-del: the default is yes | |
127 | */ | |
128 | ||
129 | int C_A_D = 1; | |
9ec52099 CLG |
130 | struct pid *cad_pid; |
131 | EXPORT_SYMBOL(cad_pid); | |
1da177e4 | 132 | |
bd804eba RW |
133 | /* |
134 | * If set, this is used for preparing the system to power off. | |
135 | */ | |
136 | ||
137 | void (*pm_power_off_prepare)(void); | |
bd804eba | 138 | |
fc832ad3 SH |
139 | /* |
140 | * Returns true if current's euid is same as p's uid or euid, | |
141 | * or has CAP_SYS_NICE to p's user_ns. | |
142 | * | |
143 | * Called with rcu_read_lock, creds are safe | |
144 | */ | |
145 | static bool set_one_prio_perm(struct task_struct *p) | |
146 | { | |
147 | const struct cred *cred = current_cred(), *pcred = __task_cred(p); | |
148 | ||
5af66203 EB |
149 | if (uid_eq(pcred->uid, cred->euid) || |
150 | uid_eq(pcred->euid, cred->euid)) | |
fc832ad3 | 151 | return true; |
c4a4d603 | 152 | if (ns_capable(pcred->user_ns, CAP_SYS_NICE)) |
fc832ad3 SH |
153 | return true; |
154 | return false; | |
155 | } | |
156 | ||
c69e8d9c DH |
157 | /* |
158 | * set the priority of a task | |
159 | * - the caller must hold the RCU read lock | |
160 | */ | |
1da177e4 LT |
161 | static int set_one_prio(struct task_struct *p, int niceval, int error) |
162 | { | |
163 | int no_nice; | |
164 | ||
fc832ad3 | 165 | if (!set_one_prio_perm(p)) { |
1da177e4 LT |
166 | error = -EPERM; |
167 | goto out; | |
168 | } | |
e43379f1 | 169 | if (niceval < task_nice(p) && !can_nice(p, niceval)) { |
1da177e4 LT |
170 | error = -EACCES; |
171 | goto out; | |
172 | } | |
173 | no_nice = security_task_setnice(p, niceval); | |
174 | if (no_nice) { | |
175 | error = no_nice; | |
176 | goto out; | |
177 | } | |
178 | if (error == -ESRCH) | |
179 | error = 0; | |
6fa3eb70 S |
180 | #ifdef CONFIG_MT_PRIO_TRACER |
181 | set_user_nice_syscall(p, niceval); | |
182 | #else | |
1da177e4 | 183 | set_user_nice(p, niceval); |
6fa3eb70 | 184 | #endif |
1da177e4 LT |
185 | out: |
186 | return error; | |
187 | } | |
188 | ||
754fe8d2 | 189 | SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) |
1da177e4 LT |
190 | { |
191 | struct task_struct *g, *p; | |
192 | struct user_struct *user; | |
86a264ab | 193 | const struct cred *cred = current_cred(); |
1da177e4 | 194 | int error = -EINVAL; |
41487c65 | 195 | struct pid *pgrp; |
7b44ab97 | 196 | kuid_t uid; |
1da177e4 | 197 | |
3e88c553 | 198 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
199 | goto out; |
200 | ||
201 | /* normalize: avoid signed division (rounding problems) */ | |
202 | error = -ESRCH; | |
203 | if (niceval < -20) | |
204 | niceval = -20; | |
205 | if (niceval > 19) | |
206 | niceval = 19; | |
207 | ||
d4581a23 | 208 | rcu_read_lock(); |
1da177e4 LT |
209 | read_lock(&tasklist_lock); |
210 | switch (which) { | |
211 | case PRIO_PROCESS: | |
41487c65 | 212 | if (who) |
228ebcbe | 213 | p = find_task_by_vpid(who); |
41487c65 EB |
214 | else |
215 | p = current; | |
1da177e4 LT |
216 | if (p) |
217 | error = set_one_prio(p, niceval, error); | |
218 | break; | |
219 | case PRIO_PGRP: | |
41487c65 | 220 | if (who) |
b488893a | 221 | pgrp = find_vpid(who); |
41487c65 EB |
222 | else |
223 | pgrp = task_pgrp(current); | |
2d70b68d | 224 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 | 225 | error = set_one_prio(p, niceval, error); |
2d70b68d | 226 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
227 | break; |
228 | case PRIO_USER: | |
7b44ab97 | 229 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 230 | user = cred->user; |
1da177e4 | 231 | if (!who) |
078de5f7 EB |
232 | uid = cred->uid; |
233 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 234 | !(user = find_user(uid))) |
86a264ab | 235 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 236 | |
dfc6a736 | 237 | do_each_thread(g, p) { |
078de5f7 | 238 | if (uid_eq(task_uid(p), uid)) |
1da177e4 | 239 | error = set_one_prio(p, niceval, error); |
dfc6a736 | 240 | } while_each_thread(g, p); |
078de5f7 | 241 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
242 | free_uid(user); /* For find_user() */ |
243 | break; | |
244 | } | |
245 | out_unlock: | |
246 | read_unlock(&tasklist_lock); | |
d4581a23 | 247 | rcu_read_unlock(); |
1da177e4 LT |
248 | out: |
249 | return error; | |
250 | } | |
251 | ||
252 | /* | |
253 | * Ugh. To avoid negative return values, "getpriority()" will | |
254 | * not return the normal nice-value, but a negated value that | |
255 | * has been offset by 20 (ie it returns 40..1 instead of -20..19) | |
256 | * to stay compatible. | |
257 | */ | |
754fe8d2 | 258 | SYSCALL_DEFINE2(getpriority, int, which, int, who) |
1da177e4 LT |
259 | { |
260 | struct task_struct *g, *p; | |
261 | struct user_struct *user; | |
86a264ab | 262 | const struct cred *cred = current_cred(); |
1da177e4 | 263 | long niceval, retval = -ESRCH; |
41487c65 | 264 | struct pid *pgrp; |
7b44ab97 | 265 | kuid_t uid; |
1da177e4 | 266 | |
3e88c553 | 267 | if (which > PRIO_USER || which < PRIO_PROCESS) |
1da177e4 LT |
268 | return -EINVAL; |
269 | ||
70118837 | 270 | rcu_read_lock(); |
1da177e4 LT |
271 | read_lock(&tasklist_lock); |
272 | switch (which) { | |
273 | case PRIO_PROCESS: | |
41487c65 | 274 | if (who) |
228ebcbe | 275 | p = find_task_by_vpid(who); |
41487c65 EB |
276 | else |
277 | p = current; | |
1da177e4 LT |
278 | if (p) { |
279 | niceval = 20 - task_nice(p); | |
280 | if (niceval > retval) | |
281 | retval = niceval; | |
282 | } | |
283 | break; | |
284 | case PRIO_PGRP: | |
41487c65 | 285 | if (who) |
b488893a | 286 | pgrp = find_vpid(who); |
41487c65 EB |
287 | else |
288 | pgrp = task_pgrp(current); | |
2d70b68d | 289 | do_each_pid_thread(pgrp, PIDTYPE_PGID, p) { |
1da177e4 LT |
290 | niceval = 20 - task_nice(p); |
291 | if (niceval > retval) | |
292 | retval = niceval; | |
2d70b68d | 293 | } while_each_pid_thread(pgrp, PIDTYPE_PGID, p); |
1da177e4 LT |
294 | break; |
295 | case PRIO_USER: | |
7b44ab97 | 296 | uid = make_kuid(cred->user_ns, who); |
74ba508f | 297 | user = cred->user; |
1da177e4 | 298 | if (!who) |
078de5f7 EB |
299 | uid = cred->uid; |
300 | else if (!uid_eq(uid, cred->uid) && | |
7b44ab97 | 301 | !(user = find_user(uid))) |
86a264ab | 302 | goto out_unlock; /* No processes for this user */ |
1da177e4 | 303 | |
dfc6a736 | 304 | do_each_thread(g, p) { |
078de5f7 | 305 | if (uid_eq(task_uid(p), uid)) { |
1da177e4 LT |
306 | niceval = 20 - task_nice(p); |
307 | if (niceval > retval) | |
308 | retval = niceval; | |
309 | } | |
dfc6a736 | 310 | } while_each_thread(g, p); |
078de5f7 | 311 | if (!uid_eq(uid, cred->uid)) |
1da177e4 LT |
312 | free_uid(user); /* for find_user() */ |
313 | break; | |
314 | } | |
315 | out_unlock: | |
316 | read_unlock(&tasklist_lock); | |
70118837 | 317 | rcu_read_unlock(); |
1da177e4 LT |
318 | |
319 | return retval; | |
320 | } | |
321 | ||
e4c94330 EB |
322 | /** |
323 | * emergency_restart - reboot the system | |
324 | * | |
325 | * Without shutting down any hardware or taking any locks | |
326 | * reboot the system. This is called when we know we are in | |
327 | * trouble so this is our best effort to reboot. This is | |
328 | * safe to call in interrupt context. | |
329 | */ | |
7c903473 EB |
330 | void emergency_restart(void) |
331 | { | |
04c6862c | 332 | kmsg_dump(KMSG_DUMP_EMERG); |
7c903473 EB |
333 | machine_emergency_restart(); |
334 | } | |
335 | EXPORT_SYMBOL_GPL(emergency_restart); | |
336 | ||
ca195b7f | 337 | void kernel_restart_prepare(char *cmd) |
4a00ea1e | 338 | { |
e041c683 | 339 | blocking_notifier_call_chain(&reboot_notifier_list, SYS_RESTART, cmd); |
4a00ea1e | 340 | system_state = SYSTEM_RESTART; |
b50fa7c8 | 341 | usermodehelper_disable(); |
4a00ea1e | 342 | device_shutdown(); |
e4c94330 | 343 | } |
1e5d5331 | 344 | |
c5f41752 AW |
345 | /** |
346 | * register_reboot_notifier - Register function to be called at reboot time | |
347 | * @nb: Info about notifier function to be called | |
348 | * | |
349 | * Registers a function with the list of functions | |
350 | * to be called at reboot time. | |
351 | * | |
352 | * Currently always returns zero, as blocking_notifier_chain_register() | |
353 | * always returns zero. | |
354 | */ | |
355 | int register_reboot_notifier(struct notifier_block *nb) | |
356 | { | |
357 | return blocking_notifier_chain_register(&reboot_notifier_list, nb); | |
358 | } | |
359 | EXPORT_SYMBOL(register_reboot_notifier); | |
360 | ||
361 | /** | |
362 | * unregister_reboot_notifier - Unregister previously registered reboot notifier | |
363 | * @nb: Hook to be unregistered | |
364 | * | |
365 | * Unregisters a previously registered reboot | |
366 | * notifier function. | |
367 | * | |
368 | * Returns zero on success, or %-ENOENT on failure. | |
369 | */ | |
370 | int unregister_reboot_notifier(struct notifier_block *nb) | |
371 | { | |
372 | return blocking_notifier_chain_unregister(&reboot_notifier_list, nb); | |
373 | } | |
374 | EXPORT_SYMBOL(unregister_reboot_notifier); | |
375 | ||
cf7df378 RH |
376 | /* Add backwards compatibility for stable trees. */ |
377 | #ifndef PF_NO_SETAFFINITY | |
378 | #define PF_NO_SETAFFINITY PF_THREAD_BOUND | |
379 | #endif | |
380 | ||
381 | static void migrate_to_reboot_cpu(void) | |
382 | { | |
383 | /* The boot cpu is always logical cpu 0 */ | |
384 | int cpu = 0; | |
385 | ||
386 | cpu_hotplug_disable(); | |
387 | ||
388 | /* Make certain the cpu I'm about to reboot on is online */ | |
389 | if (!cpu_online(cpu)) | |
390 | cpu = cpumask_first(cpu_online_mask); | |
391 | ||
392 | /* Prevent races with other tasks migrating this task */ | |
393 | current->flags |= PF_NO_SETAFFINITY; | |
394 | ||
395 | /* Make certain I only run on the appropriate processor */ | |
396 | set_cpus_allowed_ptr(current, cpumask_of(cpu)); | |
397 | } | |
398 | ||
1e5d5331 RD |
399 | /** |
400 | * kernel_restart - reboot the system | |
401 | * @cmd: pointer to buffer containing command to execute for restart | |
b8887e6e | 402 | * or %NULL |
1e5d5331 RD |
403 | * |
404 | * Shutdown everything and perform a clean reboot. | |
405 | * This is not safe to call in interrupt context. | |
406 | */ | |
e4c94330 EB |
407 | void kernel_restart(char *cmd) |
408 | { | |
409 | kernel_restart_prepare(cmd); | |
cf7df378 | 410 | migrate_to_reboot_cpu(); |
6f389a8f | 411 | syscore_shutdown(); |
756184b7 | 412 | if (!cmd) |
4a00ea1e | 413 | printk(KERN_EMERG "Restarting system.\n"); |
756184b7 | 414 | else |
4a00ea1e | 415 | printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); |
04c6862c | 416 | kmsg_dump(KMSG_DUMP_RESTART); |
4a00ea1e EB |
417 | machine_restart(cmd); |
418 | } | |
419 | EXPORT_SYMBOL_GPL(kernel_restart); | |
420 | ||
4ef7229f | 421 | static void kernel_shutdown_prepare(enum system_states state) |
729b4d4c | 422 | { |
e041c683 | 423 | blocking_notifier_call_chain(&reboot_notifier_list, |
729b4d4c AS |
424 | (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); |
425 | system_state = state; | |
b50fa7c8 | 426 | usermodehelper_disable(); |
729b4d4c AS |
427 | device_shutdown(); |
428 | } | |
e4c94330 EB |
429 | /** |
430 | * kernel_halt - halt the system | |
431 | * | |
432 | * Shutdown everything and perform a clean system halt. | |
433 | */ | |
e4c94330 EB |
434 | void kernel_halt(void) |
435 | { | |
729b4d4c | 436 | kernel_shutdown_prepare(SYSTEM_HALT); |
cf7df378 | 437 | migrate_to_reboot_cpu(); |
40dc166c | 438 | syscore_shutdown(); |
4a00ea1e | 439 | printk(KERN_EMERG "System halted.\n"); |
04c6862c | 440 | kmsg_dump(KMSG_DUMP_HALT); |
4a00ea1e EB |
441 | machine_halt(); |
442 | } | |
729b4d4c | 443 | |
4a00ea1e EB |
444 | EXPORT_SYMBOL_GPL(kernel_halt); |
445 | ||
e4c94330 EB |
446 | /** |
447 | * kernel_power_off - power_off the system | |
448 | * | |
449 | * Shutdown everything and perform a clean system power_off. | |
450 | */ | |
e4c94330 EB |
451 | void kernel_power_off(void) |
452 | { | |
729b4d4c | 453 | kernel_shutdown_prepare(SYSTEM_POWER_OFF); |
bd804eba RW |
454 | if (pm_power_off_prepare) |
455 | pm_power_off_prepare(); | |
cf7df378 | 456 | migrate_to_reboot_cpu(); |
40dc166c | 457 | syscore_shutdown(); |
4a00ea1e | 458 | printk(KERN_EMERG "Power down.\n"); |
04c6862c | 459 | kmsg_dump(KMSG_DUMP_POWEROFF); |
4a00ea1e EB |
460 | machine_power_off(); |
461 | } | |
462 | EXPORT_SYMBOL_GPL(kernel_power_off); | |
6f15fa50 TG |
463 | |
464 | static DEFINE_MUTEX(reboot_mutex); | |
465 | ||
1da177e4 LT |
466 | /* |
467 | * Reboot system call: for obvious reasons only root may call it, | |
468 | * and even root needs to set up some magic numbers in the registers | |
469 | * so that some mistake won't make this reboot the whole machine. | |
470 | * You can also set the meaning of the ctrl-alt-del-key here. | |
471 | * | |
472 | * reboot doesn't sync: do that yourself before calling this. | |
473 | */ | |
754fe8d2 HC |
474 | SYSCALL_DEFINE4(reboot, int, magic1, int, magic2, unsigned int, cmd, |
475 | void __user *, arg) | |
1da177e4 | 476 | { |
923c7538 | 477 | struct pid_namespace *pid_ns = task_active_pid_ns(current); |
1da177e4 | 478 | char buffer[256]; |
3d26dcf7 | 479 | int ret = 0; |
1da177e4 LT |
480 | |
481 | /* We only trust the superuser with rebooting the system. */ | |
923c7538 | 482 | if (!ns_capable(pid_ns->user_ns, CAP_SYS_BOOT)) |
1da177e4 LT |
483 | return -EPERM; |
484 | ||
485 | /* For safety, we require "magic" arguments. */ | |
486 | if (magic1 != LINUX_REBOOT_MAGIC1 || | |
487 | (magic2 != LINUX_REBOOT_MAGIC2 && | |
488 | magic2 != LINUX_REBOOT_MAGIC2A && | |
489 | magic2 != LINUX_REBOOT_MAGIC2B && | |
490 | magic2 != LINUX_REBOOT_MAGIC2C)) | |
491 | return -EINVAL; | |
492 | ||
cf3f8921 DL |
493 | /* |
494 | * If pid namespaces are enabled and the current task is in a child | |
495 | * pid_namespace, the command is handled by reboot_pid_ns() which will | |
496 | * call do_exit(). | |
497 | */ | |
923c7538 | 498 | ret = reboot_pid_ns(pid_ns, cmd); |
cf3f8921 DL |
499 | if (ret) |
500 | return ret; | |
501 | ||
5e38291d EB |
502 | /* Instead of trying to make the power_off code look like |
503 | * halt when pm_power_off is not set do it the easy way. | |
504 | */ | |
505 | if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off) | |
506 | cmd = LINUX_REBOOT_CMD_HALT; | |
507 | ||
6f15fa50 | 508 | mutex_lock(&reboot_mutex); |
1da177e4 LT |
509 | switch (cmd) { |
510 | case LINUX_REBOOT_CMD_RESTART: | |
4a00ea1e | 511 | kernel_restart(NULL); |
1da177e4 LT |
512 | break; |
513 | ||
514 | case LINUX_REBOOT_CMD_CAD_ON: | |
515 | C_A_D = 1; | |
516 | break; | |
517 | ||
518 | case LINUX_REBOOT_CMD_CAD_OFF: | |
519 | C_A_D = 0; | |
520 | break; | |
521 | ||
522 | case LINUX_REBOOT_CMD_HALT: | |
4a00ea1e | 523 | kernel_halt(); |
1da177e4 | 524 | do_exit(0); |
3d26dcf7 | 525 | panic("cannot halt"); |
1da177e4 LT |
526 | |
527 | case LINUX_REBOOT_CMD_POWER_OFF: | |
4a00ea1e | 528 | kernel_power_off(); |
1da177e4 LT |
529 | do_exit(0); |
530 | break; | |
531 | ||
532 | case LINUX_REBOOT_CMD_RESTART2: | |
533 | if (strncpy_from_user(&buffer[0], arg, sizeof(buffer) - 1) < 0) { | |
6f15fa50 TG |
534 | ret = -EFAULT; |
535 | break; | |
1da177e4 LT |
536 | } |
537 | buffer[sizeof(buffer) - 1] = '\0'; | |
538 | ||
4a00ea1e | 539 | kernel_restart(buffer); |
1da177e4 LT |
540 | break; |
541 | ||
3ab83521 | 542 | #ifdef CONFIG_KEXEC |
dc009d92 | 543 | case LINUX_REBOOT_CMD_KEXEC: |
3d26dcf7 AK |
544 | ret = kernel_kexec(); |
545 | break; | |
3ab83521 | 546 | #endif |
4a00ea1e | 547 | |
b0cb1a19 | 548 | #ifdef CONFIG_HIBERNATION |
1da177e4 | 549 | case LINUX_REBOOT_CMD_SW_SUSPEND: |
3d26dcf7 AK |
550 | ret = hibernate(); |
551 | break; | |
1da177e4 LT |
552 | #endif |
553 | ||
554 | default: | |
3d26dcf7 AK |
555 | ret = -EINVAL; |
556 | break; | |
1da177e4 | 557 | } |
6f15fa50 | 558 | mutex_unlock(&reboot_mutex); |
3d26dcf7 | 559 | return ret; |
1da177e4 LT |
560 | } |
561 | ||
65f27f38 | 562 | static void deferred_cad(struct work_struct *dummy) |
1da177e4 | 563 | { |
abcd9e51 | 564 | kernel_restart(NULL); |
1da177e4 LT |
565 | } |
566 | ||
567 | /* | |
568 | * This function gets called by ctrl-alt-del - ie the keyboard interrupt. | |
569 | * As it's called within an interrupt, it may NOT sync: the only choice | |
570 | * is whether to reboot at once, or just ignore the ctrl-alt-del. | |
571 | */ | |
572 | void ctrl_alt_del(void) | |
573 | { | |
65f27f38 | 574 | static DECLARE_WORK(cad_work, deferred_cad); |
1da177e4 LT |
575 | |
576 | if (C_A_D) | |
577 | schedule_work(&cad_work); | |
578 | else | |
9ec52099 | 579 | kill_cad_pid(SIGINT, 1); |
1da177e4 LT |
580 | } |
581 | ||
1da177e4 LT |
582 | /* |
583 | * Unprivileged users may change the real gid to the effective gid | |
584 | * or vice versa. (BSD-style) | |
585 | * | |
586 | * If you set the real gid at all, or set the effective gid to a value not | |
587 | * equal to the real gid, then the saved gid is set to the new effective gid. | |
588 | * | |
589 | * This makes it possible for a setgid program to completely drop its | |
590 | * privileges, which is often a useful assertion to make when you are doing | |
591 | * a security audit over a program. | |
592 | * | |
593 | * The general idea is that a program which uses just setregid() will be | |
594 | * 100% compatible with BSD. A program which uses just setgid() will be | |
595 | * 100% compatible with POSIX with saved IDs. | |
596 | * | |
597 | * SMP: There are not races, the GIDs are checked only by filesystem | |
598 | * operations (as far as semantic preservation is concerned). | |
599 | */ | |
ae1251ab | 600 | SYSCALL_DEFINE2(setregid, gid_t, rgid, gid_t, egid) |
1da177e4 | 601 | { |
a29c33f4 | 602 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
603 | const struct cred *old; |
604 | struct cred *new; | |
1da177e4 | 605 | int retval; |
a29c33f4 EB |
606 | kgid_t krgid, kegid; |
607 | ||
608 | krgid = make_kgid(ns, rgid); | |
609 | kegid = make_kgid(ns, egid); | |
610 | ||
611 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
612 | return -EINVAL; | |
613 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
614 | return -EINVAL; | |
1da177e4 | 615 | |
d84f4f99 DH |
616 | new = prepare_creds(); |
617 | if (!new) | |
618 | return -ENOMEM; | |
619 | old = current_cred(); | |
620 | ||
d84f4f99 | 621 | retval = -EPERM; |
1da177e4 | 622 | if (rgid != (gid_t) -1) { |
a29c33f4 EB |
623 | if (gid_eq(old->gid, krgid) || |
624 | gid_eq(old->egid, krgid) || | |
fc832ad3 | 625 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 626 | new->gid = krgid; |
1da177e4 | 627 | else |
d84f4f99 | 628 | goto error; |
1da177e4 LT |
629 | } |
630 | if (egid != (gid_t) -1) { | |
a29c33f4 EB |
631 | if (gid_eq(old->gid, kegid) || |
632 | gid_eq(old->egid, kegid) || | |
633 | gid_eq(old->sgid, kegid) || | |
fc832ad3 | 634 | nsown_capable(CAP_SETGID)) |
a29c33f4 | 635 | new->egid = kegid; |
756184b7 | 636 | else |
d84f4f99 | 637 | goto error; |
1da177e4 | 638 | } |
d84f4f99 | 639 | |
1da177e4 | 640 | if (rgid != (gid_t) -1 || |
a29c33f4 | 641 | (egid != (gid_t) -1 && !gid_eq(kegid, old->gid))) |
d84f4f99 DH |
642 | new->sgid = new->egid; |
643 | new->fsgid = new->egid; | |
644 | ||
645 | return commit_creds(new); | |
646 | ||
647 | error: | |
648 | abort_creds(new); | |
649 | return retval; | |
1da177e4 LT |
650 | } |
651 | ||
652 | /* | |
653 | * setgid() is implemented like SysV w/ SAVED_IDS | |
654 | * | |
655 | * SMP: Same implicit races as above. | |
656 | */ | |
ae1251ab | 657 | SYSCALL_DEFINE1(setgid, gid_t, gid) |
1da177e4 | 658 | { |
a29c33f4 | 659 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
660 | const struct cred *old; |
661 | struct cred *new; | |
1da177e4 | 662 | int retval; |
a29c33f4 EB |
663 | kgid_t kgid; |
664 | ||
665 | kgid = make_kgid(ns, gid); | |
666 | if (!gid_valid(kgid)) | |
667 | return -EINVAL; | |
1da177e4 | 668 | |
d84f4f99 DH |
669 | new = prepare_creds(); |
670 | if (!new) | |
671 | return -ENOMEM; | |
672 | old = current_cred(); | |
673 | ||
d84f4f99 | 674 | retval = -EPERM; |
fc832ad3 | 675 | if (nsown_capable(CAP_SETGID)) |
a29c33f4 EB |
676 | new->gid = new->egid = new->sgid = new->fsgid = kgid; |
677 | else if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->sgid)) | |
678 | new->egid = new->fsgid = kgid; | |
1da177e4 | 679 | else |
d84f4f99 | 680 | goto error; |
1da177e4 | 681 | |
d84f4f99 DH |
682 | return commit_creds(new); |
683 | ||
684 | error: | |
685 | abort_creds(new); | |
686 | return retval; | |
1da177e4 | 687 | } |
54e99124 | 688 | |
d84f4f99 DH |
689 | /* |
690 | * change the user struct in a credentials set to match the new UID | |
691 | */ | |
692 | static int set_user(struct cred *new) | |
1da177e4 LT |
693 | { |
694 | struct user_struct *new_user; | |
695 | ||
078de5f7 | 696 | new_user = alloc_uid(new->uid); |
1da177e4 LT |
697 | if (!new_user) |
698 | return -EAGAIN; | |
699 | ||
72fa5997 VK |
700 | /* |
701 | * We don't fail in case of NPROC limit excess here because too many | |
702 | * poorly written programs don't check set*uid() return code, assuming | |
703 | * it never fails if called by root. We may still enforce NPROC limit | |
704 | * for programs doing set*uid()+execve() by harmlessly deferring the | |
705 | * failure to the execve() stage. | |
706 | */ | |
78d7d407 | 707 | if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) && |
72fa5997 VK |
708 | new_user != INIT_USER) |
709 | current->flags |= PF_NPROC_EXCEEDED; | |
710 | else | |
711 | current->flags &= ~PF_NPROC_EXCEEDED; | |
1da177e4 | 712 | |
d84f4f99 DH |
713 | free_uid(new->user); |
714 | new->user = new_user; | |
1da177e4 LT |
715 | return 0; |
716 | } | |
717 | ||
718 | /* | |
719 | * Unprivileged users may change the real uid to the effective uid | |
720 | * or vice versa. (BSD-style) | |
721 | * | |
722 | * If you set the real uid at all, or set the effective uid to a value not | |
723 | * equal to the real uid, then the saved uid is set to the new effective uid. | |
724 | * | |
725 | * This makes it possible for a setuid program to completely drop its | |
726 | * privileges, which is often a useful assertion to make when you are doing | |
727 | * a security audit over a program. | |
728 | * | |
729 | * The general idea is that a program which uses just setreuid() will be | |
730 | * 100% compatible with BSD. A program which uses just setuid() will be | |
731 | * 100% compatible with POSIX with saved IDs. | |
732 | */ | |
ae1251ab | 733 | SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) |
1da177e4 | 734 | { |
a29c33f4 | 735 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
736 | const struct cred *old; |
737 | struct cred *new; | |
1da177e4 | 738 | int retval; |
a29c33f4 EB |
739 | kuid_t kruid, keuid; |
740 | ||
741 | kruid = make_kuid(ns, ruid); | |
742 | keuid = make_kuid(ns, euid); | |
743 | ||
744 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
745 | return -EINVAL; | |
746 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
747 | return -EINVAL; | |
1da177e4 | 748 | |
d84f4f99 DH |
749 | new = prepare_creds(); |
750 | if (!new) | |
751 | return -ENOMEM; | |
752 | old = current_cred(); | |
753 | ||
d84f4f99 | 754 | retval = -EPERM; |
1da177e4 | 755 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
756 | new->uid = kruid; |
757 | if (!uid_eq(old->uid, kruid) && | |
758 | !uid_eq(old->euid, kruid) && | |
fc832ad3 | 759 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 760 | goto error; |
1da177e4 LT |
761 | } |
762 | ||
763 | if (euid != (uid_t) -1) { | |
a29c33f4 EB |
764 | new->euid = keuid; |
765 | if (!uid_eq(old->uid, keuid) && | |
766 | !uid_eq(old->euid, keuid) && | |
767 | !uid_eq(old->suid, keuid) && | |
fc832ad3 | 768 | !nsown_capable(CAP_SETUID)) |
d84f4f99 | 769 | goto error; |
1da177e4 LT |
770 | } |
771 | ||
a29c33f4 | 772 | if (!uid_eq(new->uid, old->uid)) { |
54e99124 DG |
773 | retval = set_user(new); |
774 | if (retval < 0) | |
775 | goto error; | |
776 | } | |
1da177e4 | 777 | if (ruid != (uid_t) -1 || |
a29c33f4 | 778 | (euid != (uid_t) -1 && !uid_eq(keuid, old->uid))) |
d84f4f99 DH |
779 | new->suid = new->euid; |
780 | new->fsuid = new->euid; | |
1da177e4 | 781 | |
d84f4f99 DH |
782 | retval = security_task_fix_setuid(new, old, LSM_SETID_RE); |
783 | if (retval < 0) | |
784 | goto error; | |
1da177e4 | 785 | |
d84f4f99 | 786 | return commit_creds(new); |
1da177e4 | 787 | |
d84f4f99 DH |
788 | error: |
789 | abort_creds(new); | |
790 | return retval; | |
791 | } | |
1da177e4 LT |
792 | |
793 | /* | |
794 | * setuid() is implemented like SysV with SAVED_IDS | |
795 | * | |
796 | * Note that SAVED_ID's is deficient in that a setuid root program | |
797 | * like sendmail, for example, cannot set its uid to be a normal | |
798 | * user and then switch back, because if you're root, setuid() sets | |
799 | * the saved uid too. If you don't like this, blame the bright people | |
800 | * in the POSIX committee and/or USG. Note that the BSD-style setreuid() | |
801 | * will allow a root program to temporarily drop privileges and be able to | |
802 | * regain them by swapping the real and effective uid. | |
803 | */ | |
ae1251ab | 804 | SYSCALL_DEFINE1(setuid, uid_t, uid) |
1da177e4 | 805 | { |
a29c33f4 | 806 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
807 | const struct cred *old; |
808 | struct cred *new; | |
1da177e4 | 809 | int retval; |
a29c33f4 EB |
810 | kuid_t kuid; |
811 | ||
812 | kuid = make_kuid(ns, uid); | |
813 | if (!uid_valid(kuid)) | |
814 | return -EINVAL; | |
1da177e4 | 815 | |
d84f4f99 DH |
816 | new = prepare_creds(); |
817 | if (!new) | |
818 | return -ENOMEM; | |
819 | old = current_cred(); | |
820 | ||
d84f4f99 | 821 | retval = -EPERM; |
fc832ad3 | 822 | if (nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
823 | new->suid = new->uid = kuid; |
824 | if (!uid_eq(kuid, old->uid)) { | |
54e99124 DG |
825 | retval = set_user(new); |
826 | if (retval < 0) | |
827 | goto error; | |
d84f4f99 | 828 | } |
a29c33f4 | 829 | } else if (!uid_eq(kuid, old->uid) && !uid_eq(kuid, new->suid)) { |
d84f4f99 | 830 | goto error; |
1da177e4 | 831 | } |
1da177e4 | 832 | |
a29c33f4 | 833 | new->fsuid = new->euid = kuid; |
d84f4f99 DH |
834 | |
835 | retval = security_task_fix_setuid(new, old, LSM_SETID_ID); | |
836 | if (retval < 0) | |
837 | goto error; | |
1da177e4 | 838 | |
d84f4f99 | 839 | return commit_creds(new); |
1da177e4 | 840 | |
d84f4f99 DH |
841 | error: |
842 | abort_creds(new); | |
843 | return retval; | |
1da177e4 LT |
844 | } |
845 | ||
846 | ||
847 | /* | |
848 | * This function implements a generic ability to update ruid, euid, | |
849 | * and suid. This allows you to implement the 4.4 compatible seteuid(). | |
850 | */ | |
ae1251ab | 851 | SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) |
1da177e4 | 852 | { |
a29c33f4 | 853 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
854 | const struct cred *old; |
855 | struct cred *new; | |
1da177e4 | 856 | int retval; |
a29c33f4 EB |
857 | kuid_t kruid, keuid, ksuid; |
858 | ||
859 | kruid = make_kuid(ns, ruid); | |
860 | keuid = make_kuid(ns, euid); | |
861 | ksuid = make_kuid(ns, suid); | |
862 | ||
863 | if ((ruid != (uid_t) -1) && !uid_valid(kruid)) | |
864 | return -EINVAL; | |
865 | ||
866 | if ((euid != (uid_t) -1) && !uid_valid(keuid)) | |
867 | return -EINVAL; | |
868 | ||
869 | if ((suid != (uid_t) -1) && !uid_valid(ksuid)) | |
870 | return -EINVAL; | |
1da177e4 | 871 | |
d84f4f99 DH |
872 | new = prepare_creds(); |
873 | if (!new) | |
874 | return -ENOMEM; | |
875 | ||
d84f4f99 | 876 | old = current_cred(); |
1da177e4 | 877 | |
d84f4f99 | 878 | retval = -EPERM; |
fc832ad3 | 879 | if (!nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
880 | if (ruid != (uid_t) -1 && !uid_eq(kruid, old->uid) && |
881 | !uid_eq(kruid, old->euid) && !uid_eq(kruid, old->suid)) | |
d84f4f99 | 882 | goto error; |
a29c33f4 EB |
883 | if (euid != (uid_t) -1 && !uid_eq(keuid, old->uid) && |
884 | !uid_eq(keuid, old->euid) && !uid_eq(keuid, old->suid)) | |
d84f4f99 | 885 | goto error; |
a29c33f4 EB |
886 | if (suid != (uid_t) -1 && !uid_eq(ksuid, old->uid) && |
887 | !uid_eq(ksuid, old->euid) && !uid_eq(ksuid, old->suid)) | |
d84f4f99 | 888 | goto error; |
1da177e4 | 889 | } |
d84f4f99 | 890 | |
1da177e4 | 891 | if (ruid != (uid_t) -1) { |
a29c33f4 EB |
892 | new->uid = kruid; |
893 | if (!uid_eq(kruid, old->uid)) { | |
54e99124 DG |
894 | retval = set_user(new); |
895 | if (retval < 0) | |
896 | goto error; | |
897 | } | |
1da177e4 | 898 | } |
d84f4f99 | 899 | if (euid != (uid_t) -1) |
a29c33f4 | 900 | new->euid = keuid; |
1da177e4 | 901 | if (suid != (uid_t) -1) |
a29c33f4 | 902 | new->suid = ksuid; |
d84f4f99 | 903 | new->fsuid = new->euid; |
1da177e4 | 904 | |
d84f4f99 DH |
905 | retval = security_task_fix_setuid(new, old, LSM_SETID_RES); |
906 | if (retval < 0) | |
907 | goto error; | |
1da177e4 | 908 | |
d84f4f99 | 909 | return commit_creds(new); |
1da177e4 | 910 | |
d84f4f99 DH |
911 | error: |
912 | abort_creds(new); | |
913 | return retval; | |
1da177e4 LT |
914 | } |
915 | ||
a29c33f4 | 916 | SYSCALL_DEFINE3(getresuid, uid_t __user *, ruidp, uid_t __user *, euidp, uid_t __user *, suidp) |
1da177e4 | 917 | { |
86a264ab | 918 | const struct cred *cred = current_cred(); |
1da177e4 | 919 | int retval; |
a29c33f4 EB |
920 | uid_t ruid, euid, suid; |
921 | ||
922 | ruid = from_kuid_munged(cred->user_ns, cred->uid); | |
923 | euid = from_kuid_munged(cred->user_ns, cred->euid); | |
924 | suid = from_kuid_munged(cred->user_ns, cred->suid); | |
1da177e4 | 925 | |
a29c33f4 EB |
926 | if (!(retval = put_user(ruid, ruidp)) && |
927 | !(retval = put_user(euid, euidp))) | |
928 | retval = put_user(suid, suidp); | |
1da177e4 LT |
929 | |
930 | return retval; | |
931 | } | |
932 | ||
933 | /* | |
934 | * Same as above, but for rgid, egid, sgid. | |
935 | */ | |
ae1251ab | 936 | SYSCALL_DEFINE3(setresgid, gid_t, rgid, gid_t, egid, gid_t, sgid) |
1da177e4 | 937 | { |
a29c33f4 | 938 | struct user_namespace *ns = current_user_ns(); |
d84f4f99 DH |
939 | const struct cred *old; |
940 | struct cred *new; | |
1da177e4 | 941 | int retval; |
a29c33f4 EB |
942 | kgid_t krgid, kegid, ksgid; |
943 | ||
944 | krgid = make_kgid(ns, rgid); | |
945 | kegid = make_kgid(ns, egid); | |
946 | ksgid = make_kgid(ns, sgid); | |
947 | ||
948 | if ((rgid != (gid_t) -1) && !gid_valid(krgid)) | |
949 | return -EINVAL; | |
950 | if ((egid != (gid_t) -1) && !gid_valid(kegid)) | |
951 | return -EINVAL; | |
952 | if ((sgid != (gid_t) -1) && !gid_valid(ksgid)) | |
953 | return -EINVAL; | |
1da177e4 | 954 | |
d84f4f99 DH |
955 | new = prepare_creds(); |
956 | if (!new) | |
957 | return -ENOMEM; | |
958 | old = current_cred(); | |
959 | ||
d84f4f99 | 960 | retval = -EPERM; |
fc832ad3 | 961 | if (!nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
962 | if (rgid != (gid_t) -1 && !gid_eq(krgid, old->gid) && |
963 | !gid_eq(krgid, old->egid) && !gid_eq(krgid, old->sgid)) | |
d84f4f99 | 964 | goto error; |
a29c33f4 EB |
965 | if (egid != (gid_t) -1 && !gid_eq(kegid, old->gid) && |
966 | !gid_eq(kegid, old->egid) && !gid_eq(kegid, old->sgid)) | |
d84f4f99 | 967 | goto error; |
a29c33f4 EB |
968 | if (sgid != (gid_t) -1 && !gid_eq(ksgid, old->gid) && |
969 | !gid_eq(ksgid, old->egid) && !gid_eq(ksgid, old->sgid)) | |
d84f4f99 | 970 | goto error; |
1da177e4 | 971 | } |
d84f4f99 | 972 | |
1da177e4 | 973 | if (rgid != (gid_t) -1) |
a29c33f4 | 974 | new->gid = krgid; |
d84f4f99 | 975 | if (egid != (gid_t) -1) |
a29c33f4 | 976 | new->egid = kegid; |
1da177e4 | 977 | if (sgid != (gid_t) -1) |
a29c33f4 | 978 | new->sgid = ksgid; |
d84f4f99 | 979 | new->fsgid = new->egid; |
1da177e4 | 980 | |
d84f4f99 DH |
981 | return commit_creds(new); |
982 | ||
983 | error: | |
984 | abort_creds(new); | |
985 | return retval; | |
1da177e4 LT |
986 | } |
987 | ||
a29c33f4 | 988 | SYSCALL_DEFINE3(getresgid, gid_t __user *, rgidp, gid_t __user *, egidp, gid_t __user *, sgidp) |
1da177e4 | 989 | { |
86a264ab | 990 | const struct cred *cred = current_cred(); |
1da177e4 | 991 | int retval; |
a29c33f4 EB |
992 | gid_t rgid, egid, sgid; |
993 | ||
994 | rgid = from_kgid_munged(cred->user_ns, cred->gid); | |
995 | egid = from_kgid_munged(cred->user_ns, cred->egid); | |
996 | sgid = from_kgid_munged(cred->user_ns, cred->sgid); | |
1da177e4 | 997 | |
a29c33f4 EB |
998 | if (!(retval = put_user(rgid, rgidp)) && |
999 | !(retval = put_user(egid, egidp))) | |
1000 | retval = put_user(sgid, sgidp); | |
1da177e4 LT |
1001 | |
1002 | return retval; | |
1003 | } | |
1004 | ||
1005 | ||
1006 | /* | |
1007 | * "setfsuid()" sets the fsuid - the uid used for filesystem checks. This | |
1008 | * is used for "access()" and for the NFS daemon (letting nfsd stay at | |
1009 | * whatever uid it wants to). It normally shadows "euid", except when | |
1010 | * explicitly set by setfsuid() or for access.. | |
1011 | */ | |
ae1251ab | 1012 | SYSCALL_DEFINE1(setfsuid, uid_t, uid) |
1da177e4 | 1013 | { |
d84f4f99 DH |
1014 | const struct cred *old; |
1015 | struct cred *new; | |
1016 | uid_t old_fsuid; | |
a29c33f4 EB |
1017 | kuid_t kuid; |
1018 | ||
1019 | old = current_cred(); | |
1020 | old_fsuid = from_kuid_munged(old->user_ns, old->fsuid); | |
1021 | ||
1022 | kuid = make_kuid(old->user_ns, uid); | |
1023 | if (!uid_valid(kuid)) | |
1024 | return old_fsuid; | |
1da177e4 | 1025 | |
d84f4f99 DH |
1026 | new = prepare_creds(); |
1027 | if (!new) | |
a29c33f4 | 1028 | return old_fsuid; |
1da177e4 | 1029 | |
a29c33f4 EB |
1030 | if (uid_eq(kuid, old->uid) || uid_eq(kuid, old->euid) || |
1031 | uid_eq(kuid, old->suid) || uid_eq(kuid, old->fsuid) || | |
fc832ad3 | 1032 | nsown_capable(CAP_SETUID)) { |
a29c33f4 EB |
1033 | if (!uid_eq(kuid, old->fsuid)) { |
1034 | new->fsuid = kuid; | |
d84f4f99 DH |
1035 | if (security_task_fix_setuid(new, old, LSM_SETID_FS) == 0) |
1036 | goto change_okay; | |
1da177e4 | 1037 | } |
1da177e4 LT |
1038 | } |
1039 | ||
d84f4f99 DH |
1040 | abort_creds(new); |
1041 | return old_fsuid; | |
1da177e4 | 1042 | |
d84f4f99 DH |
1043 | change_okay: |
1044 | commit_creds(new); | |
1da177e4 LT |
1045 | return old_fsuid; |
1046 | } | |
1047 | ||
1048 | /* | |
6fa3eb70 | 1049 | * Samma pa svenska.. |
1da177e4 | 1050 | */ |
ae1251ab | 1051 | SYSCALL_DEFINE1(setfsgid, gid_t, gid) |
1da177e4 | 1052 | { |
d84f4f99 DH |
1053 | const struct cred *old; |
1054 | struct cred *new; | |
1055 | gid_t old_fsgid; | |
a29c33f4 EB |
1056 | kgid_t kgid; |
1057 | ||
1058 | old = current_cred(); | |
1059 | old_fsgid = from_kgid_munged(old->user_ns, old->fsgid); | |
1060 | ||
1061 | kgid = make_kgid(old->user_ns, gid); | |
1062 | if (!gid_valid(kgid)) | |
1063 | return old_fsgid; | |
d84f4f99 DH |
1064 | |
1065 | new = prepare_creds(); | |
1066 | if (!new) | |
a29c33f4 | 1067 | return old_fsgid; |
1da177e4 | 1068 | |
a29c33f4 EB |
1069 | if (gid_eq(kgid, old->gid) || gid_eq(kgid, old->egid) || |
1070 | gid_eq(kgid, old->sgid) || gid_eq(kgid, old->fsgid) || | |
fc832ad3 | 1071 | nsown_capable(CAP_SETGID)) { |
a29c33f4 EB |
1072 | if (!gid_eq(kgid, old->fsgid)) { |
1073 | new->fsgid = kgid; | |
d84f4f99 | 1074 | goto change_okay; |
1da177e4 | 1075 | } |
1da177e4 | 1076 | } |
d84f4f99 | 1077 | |
d84f4f99 DH |
1078 | abort_creds(new); |
1079 | return old_fsgid; | |
1080 | ||
1081 | change_okay: | |
1082 | commit_creds(new); | |
1da177e4 LT |
1083 | return old_fsgid; |
1084 | } | |
1085 | ||
4a22f166 SR |
1086 | /** |
1087 | * sys_getpid - return the thread group id of the current process | |
1088 | * | |
1089 | * Note, despite the name, this returns the tgid not the pid. The tgid and | |
1090 | * the pid are identical unless CLONE_THREAD was specified on clone() in | |
1091 | * which case the tgid is the same in all threads of the same group. | |
1092 | * | |
1093 | * This is SMP safe as current->tgid does not change. | |
1094 | */ | |
1095 | SYSCALL_DEFINE0(getpid) | |
1096 | { | |
1097 | return task_tgid_vnr(current); | |
1098 | } | |
1099 | ||
1100 | /* Thread ID - the internal kernel "pid" */ | |
1101 | SYSCALL_DEFINE0(gettid) | |
1102 | { | |
1103 | return task_pid_vnr(current); | |
1104 | } | |
1105 | ||
1106 | /* | |
1107 | * Accessing ->real_parent is not SMP-safe, it could | |
1108 | * change from under us. However, we can use a stale | |
1109 | * value of ->real_parent under rcu_read_lock(), see | |
1110 | * release_task()->call_rcu(delayed_put_task_struct). | |
1111 | */ | |
1112 | SYSCALL_DEFINE0(getppid) | |
1113 | { | |
1114 | int pid; | |
1115 | ||
1116 | rcu_read_lock(); | |
1117 | pid = task_tgid_vnr(rcu_dereference(current->real_parent)); | |
1118 | rcu_read_unlock(); | |
1119 | ||
1120 | return pid; | |
1121 | } | |
1122 | ||
1123 | SYSCALL_DEFINE0(getuid) | |
1124 | { | |
1125 | /* Only we change this so SMP safe */ | |
1126 | return from_kuid_munged(current_user_ns(), current_uid()); | |
1127 | } | |
1128 | ||
1129 | SYSCALL_DEFINE0(geteuid) | |
1130 | { | |
1131 | /* Only we change this so SMP safe */ | |
1132 | return from_kuid_munged(current_user_ns(), current_euid()); | |
1133 | } | |
1134 | ||
1135 | SYSCALL_DEFINE0(getgid) | |
1136 | { | |
1137 | /* Only we change this so SMP safe */ | |
1138 | return from_kgid_munged(current_user_ns(), current_gid()); | |
1139 | } | |
1140 | ||
1141 | SYSCALL_DEFINE0(getegid) | |
1142 | { | |
1143 | /* Only we change this so SMP safe */ | |
1144 | return from_kgid_munged(current_user_ns(), current_egid()); | |
1145 | } | |
1146 | ||
f06febc9 FM |
1147 | void do_sys_times(struct tms *tms) |
1148 | { | |
0cf55e1e | 1149 | cputime_t tgutime, tgstime, cutime, cstime; |
f06febc9 | 1150 | |
2b5fe6de | 1151 | spin_lock_irq(¤t->sighand->siglock); |
e80d0a1a | 1152 | thread_group_cputime_adjusted(current, &tgutime, &tgstime); |
f06febc9 FM |
1153 | cutime = current->signal->cutime; |
1154 | cstime = current->signal->cstime; | |
1155 | spin_unlock_irq(¤t->sighand->siglock); | |
0cf55e1e HS |
1156 | tms->tms_utime = cputime_to_clock_t(tgutime); |
1157 | tms->tms_stime = cputime_to_clock_t(tgstime); | |
f06febc9 FM |
1158 | tms->tms_cutime = cputime_to_clock_t(cutime); |
1159 | tms->tms_cstime = cputime_to_clock_t(cstime); | |
1160 | } | |
1161 | ||
58fd3aa2 | 1162 | SYSCALL_DEFINE1(times, struct tms __user *, tbuf) |
1da177e4 | 1163 | { |
1da177e4 LT |
1164 | if (tbuf) { |
1165 | struct tms tmp; | |
f06febc9 FM |
1166 | |
1167 | do_sys_times(&tmp); | |
1da177e4 LT |
1168 | if (copy_to_user(tbuf, &tmp, sizeof(struct tms))) |
1169 | return -EFAULT; | |
1170 | } | |
e3d5a27d | 1171 | force_successful_syscall_return(); |
1da177e4 LT |
1172 | return (long) jiffies_64_to_clock_t(get_jiffies_64()); |
1173 | } | |
1174 | ||
1175 | /* | |
1176 | * This needs some heavy checking ... | |
1177 | * I just haven't the stomach for it. I also don't fully | |
1178 | * understand sessions/pgrp etc. Let somebody who does explain it. | |
1179 | * | |
1180 | * OK, I think I have the protection semantics right.... this is really | |
1181 | * only important on a multi-user system anyway, to make sure one user | |
1182 | * can't send a signal to a process owned by another. -TYT, 12/12/91 | |
1183 | * | |
1184 | * Auch. Had to add the 'did_exec' flag to conform completely to POSIX. | |
1185 | * LBT 04.03.94 | |
1186 | */ | |
b290ebe2 | 1187 | SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) |
1da177e4 LT |
1188 | { |
1189 | struct task_struct *p; | |
ee0acf90 | 1190 | struct task_struct *group_leader = current->group_leader; |
4e021306 ON |
1191 | struct pid *pgrp; |
1192 | int err; | |
1da177e4 LT |
1193 | |
1194 | if (!pid) | |
b488893a | 1195 | pid = task_pid_vnr(group_leader); |
1da177e4 LT |
1196 | if (!pgid) |
1197 | pgid = pid; | |
1198 | if (pgid < 0) | |
1199 | return -EINVAL; | |
950eaaca | 1200 | rcu_read_lock(); |
1da177e4 LT |
1201 | |
1202 | /* From this point forward we keep holding onto the tasklist lock | |
1203 | * so that our parent does not change from under us. -DaveM | |
1204 | */ | |
1205 | write_lock_irq(&tasklist_lock); | |
1206 | ||
1207 | err = -ESRCH; | |
4e021306 | 1208 | p = find_task_by_vpid(pid); |
1da177e4 LT |
1209 | if (!p) |
1210 | goto out; | |
1211 | ||
1212 | err = -EINVAL; | |
1213 | if (!thread_group_leader(p)) | |
1214 | goto out; | |
1215 | ||
4e021306 | 1216 | if (same_thread_group(p->real_parent, group_leader)) { |
1da177e4 | 1217 | err = -EPERM; |
41487c65 | 1218 | if (task_session(p) != task_session(group_leader)) |
1da177e4 LT |
1219 | goto out; |
1220 | err = -EACCES; | |
1221 | if (p->did_exec) | |
1222 | goto out; | |
1223 | } else { | |
1224 | err = -ESRCH; | |
ee0acf90 | 1225 | if (p != group_leader) |
1da177e4 LT |
1226 | goto out; |
1227 | } | |
1228 | ||
1229 | err = -EPERM; | |
1230 | if (p->signal->leader) | |
1231 | goto out; | |
1232 | ||
4e021306 | 1233 | pgrp = task_pid(p); |
1da177e4 | 1234 | if (pgid != pid) { |
b488893a | 1235 | struct task_struct *g; |
1da177e4 | 1236 | |
4e021306 ON |
1237 | pgrp = find_vpid(pgid); |
1238 | g = pid_task(pgrp, PIDTYPE_PGID); | |
41487c65 | 1239 | if (!g || task_session(g) != task_session(group_leader)) |
f020bc46 | 1240 | goto out; |
1da177e4 LT |
1241 | } |
1242 | ||
1da177e4 LT |
1243 | err = security_task_setpgid(p, pgid); |
1244 | if (err) | |
1245 | goto out; | |
1246 | ||
1b0f7ffd | 1247 | if (task_pgrp(p) != pgrp) |
83beaf3c | 1248 | change_pid(p, PIDTYPE_PGID, pgrp); |
1da177e4 LT |
1249 | |
1250 | err = 0; | |
1251 | out: | |
1252 | /* All paths lead to here, thus we are safe. -DaveM */ | |
1253 | write_unlock_irq(&tasklist_lock); | |
950eaaca | 1254 | rcu_read_unlock(); |
1da177e4 LT |
1255 | return err; |
1256 | } | |
1257 | ||
dbf040d9 | 1258 | SYSCALL_DEFINE1(getpgid, pid_t, pid) |
1da177e4 | 1259 | { |
12a3de0a ON |
1260 | struct task_struct *p; |
1261 | struct pid *grp; | |
1262 | int retval; | |
1263 | ||
1264 | rcu_read_lock(); | |
756184b7 | 1265 | if (!pid) |
12a3de0a | 1266 | grp = task_pgrp(current); |
756184b7 | 1267 | else { |
1da177e4 | 1268 | retval = -ESRCH; |
12a3de0a ON |
1269 | p = find_task_by_vpid(pid); |
1270 | if (!p) | |
1271 | goto out; | |
1272 | grp = task_pgrp(p); | |
1273 | if (!grp) | |
1274 | goto out; | |
1275 | ||
1276 | retval = security_task_getpgid(p); | |
1277 | if (retval) | |
1278 | goto out; | |
1da177e4 | 1279 | } |
12a3de0a ON |
1280 | retval = pid_vnr(grp); |
1281 | out: | |
1282 | rcu_read_unlock(); | |
1283 | return retval; | |
1da177e4 LT |
1284 | } |
1285 | ||
1286 | #ifdef __ARCH_WANT_SYS_GETPGRP | |
1287 | ||
dbf040d9 | 1288 | SYSCALL_DEFINE0(getpgrp) |
1da177e4 | 1289 | { |
12a3de0a | 1290 | return sys_getpgid(0); |
1da177e4 LT |
1291 | } |
1292 | ||
1293 | #endif | |
1294 | ||
dbf040d9 | 1295 | SYSCALL_DEFINE1(getsid, pid_t, pid) |
1da177e4 | 1296 | { |
1dd768c0 ON |
1297 | struct task_struct *p; |
1298 | struct pid *sid; | |
1299 | int retval; | |
1300 | ||
1301 | rcu_read_lock(); | |
756184b7 | 1302 | if (!pid) |
1dd768c0 | 1303 | sid = task_session(current); |
756184b7 | 1304 | else { |
1da177e4 | 1305 | retval = -ESRCH; |
1dd768c0 ON |
1306 | p = find_task_by_vpid(pid); |
1307 | if (!p) | |
1308 | goto out; | |
1309 | sid = task_session(p); | |
1310 | if (!sid) | |
1311 | goto out; | |
1312 | ||
1313 | retval = security_task_getsid(p); | |
1314 | if (retval) | |
1315 | goto out; | |
1da177e4 | 1316 | } |
1dd768c0 ON |
1317 | retval = pid_vnr(sid); |
1318 | out: | |
1319 | rcu_read_unlock(); | |
1320 | return retval; | |
1da177e4 LT |
1321 | } |
1322 | ||
b290ebe2 | 1323 | SYSCALL_DEFINE0(setsid) |
1da177e4 | 1324 | { |
e19f247a | 1325 | struct task_struct *group_leader = current->group_leader; |
e4cc0a9c ON |
1326 | struct pid *sid = task_pid(group_leader); |
1327 | pid_t session = pid_vnr(sid); | |
1da177e4 LT |
1328 | int err = -EPERM; |
1329 | ||
1da177e4 | 1330 | write_lock_irq(&tasklist_lock); |
390e2ff0 EB |
1331 | /* Fail if I am already a session leader */ |
1332 | if (group_leader->signal->leader) | |
1333 | goto out; | |
1334 | ||
430c6231 ON |
1335 | /* Fail if a process group id already exists that equals the |
1336 | * proposed session id. | |
390e2ff0 | 1337 | */ |
6806aac6 | 1338 | if (pid_task(sid, PIDTYPE_PGID)) |
1da177e4 LT |
1339 | goto out; |
1340 | ||
e19f247a | 1341 | group_leader->signal->leader = 1; |
8520d7c7 | 1342 | __set_special_pids(sid); |
24ec839c | 1343 | |
9c9f4ded | 1344 | proc_clear_tty(group_leader); |
24ec839c | 1345 | |
e4cc0a9c | 1346 | err = session; |
1da177e4 LT |
1347 | out: |
1348 | write_unlock_irq(&tasklist_lock); | |
5091faa4 | 1349 | if (err > 0) { |
0d0df599 | 1350 | proc_sid_connector(group_leader); |
5091faa4 MG |
1351 | sched_autogroup_create_attach(group_leader); |
1352 | } | |
1da177e4 LT |
1353 | return err; |
1354 | } | |
1355 | ||
1da177e4 LT |
1356 | DECLARE_RWSEM(uts_sem); |
1357 | ||
e28cbf22 CH |
1358 | #ifdef COMPAT_UTS_MACHINE |
1359 | #define override_architecture(name) \ | |
46da2766 | 1360 | (personality(current->personality) == PER_LINUX32 && \ |
e28cbf22 CH |
1361 | copy_to_user(name->machine, COMPAT_UTS_MACHINE, \ |
1362 | sizeof(COMPAT_UTS_MACHINE))) | |
1363 | #else | |
1364 | #define override_architecture(name) 0 | |
1365 | #endif | |
1366 | ||
be27425d AK |
1367 | /* |
1368 | * Work around broken programs that cannot handle "Linux 3.0". | |
1369 | * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40 | |
1370 | */ | |
2702b152 | 1371 | static int override_release(char __user *release, size_t len) |
be27425d AK |
1372 | { |
1373 | int ret = 0; | |
be27425d AK |
1374 | |
1375 | if (current->personality & UNAME26) { | |
2702b152 KC |
1376 | const char *rest = UTS_RELEASE; |
1377 | char buf[65] = { 0 }; | |
be27425d AK |
1378 | int ndots = 0; |
1379 | unsigned v; | |
2702b152 | 1380 | size_t copy; |
be27425d AK |
1381 | |
1382 | while (*rest) { | |
1383 | if (*rest == '.' && ++ndots >= 3) | |
1384 | break; | |
1385 | if (!isdigit(*rest) && *rest != '.') | |
1386 | break; | |
1387 | rest++; | |
1388 | } | |
1389 | v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40; | |
31fd84b9 | 1390 | copy = clamp_t(size_t, len, 1, sizeof(buf)); |
2702b152 KC |
1391 | copy = scnprintf(buf, copy, "2.6.%u%s", v, rest); |
1392 | ret = copy_to_user(release, buf, copy + 1); | |
be27425d AK |
1393 | } |
1394 | return ret; | |
1395 | } | |
1396 | ||
e48fbb69 | 1397 | SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name) |
1da177e4 LT |
1398 | { |
1399 | int errno = 0; | |
1400 | ||
1401 | down_read(&uts_sem); | |
e9ff3990 | 1402 | if (copy_to_user(name, utsname(), sizeof *name)) |
1da177e4 LT |
1403 | errno = -EFAULT; |
1404 | up_read(&uts_sem); | |
e28cbf22 | 1405 | |
be27425d AK |
1406 | if (!errno && override_release(name->release, sizeof(name->release))) |
1407 | errno = -EFAULT; | |
e28cbf22 CH |
1408 | if (!errno && override_architecture(name)) |
1409 | errno = -EFAULT; | |
1da177e4 LT |
1410 | return errno; |
1411 | } | |
1412 | ||
5cacdb4a CH |
1413 | #ifdef __ARCH_WANT_SYS_OLD_UNAME |
1414 | /* | |
1415 | * Old cruft | |
1416 | */ | |
1417 | SYSCALL_DEFINE1(uname, struct old_utsname __user *, name) | |
1418 | { | |
1419 | int error = 0; | |
1420 | ||
1421 | if (!name) | |
1422 | return -EFAULT; | |
1423 | ||
1424 | down_read(&uts_sem); | |
1425 | if (copy_to_user(name, utsname(), sizeof(*name))) | |
1426 | error = -EFAULT; | |
1427 | up_read(&uts_sem); | |
1428 | ||
be27425d AK |
1429 | if (!error && override_release(name->release, sizeof(name->release))) |
1430 | error = -EFAULT; | |
5cacdb4a CH |
1431 | if (!error && override_architecture(name)) |
1432 | error = -EFAULT; | |
1433 | return error; | |
1434 | } | |
1435 | ||
1436 | SYSCALL_DEFINE1(olduname, struct oldold_utsname __user *, name) | |
1437 | { | |
1438 | int error; | |
1439 | ||
1440 | if (!name) | |
1441 | return -EFAULT; | |
1442 | if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname))) | |
1443 | return -EFAULT; | |
1444 | ||
1445 | down_read(&uts_sem); | |
1446 | error = __copy_to_user(&name->sysname, &utsname()->sysname, | |
1447 | __OLD_UTS_LEN); | |
1448 | error |= __put_user(0, name->sysname + __OLD_UTS_LEN); | |
1449 | error |= __copy_to_user(&name->nodename, &utsname()->nodename, | |
1450 | __OLD_UTS_LEN); | |
1451 | error |= __put_user(0, name->nodename + __OLD_UTS_LEN); | |
1452 | error |= __copy_to_user(&name->release, &utsname()->release, | |
1453 | __OLD_UTS_LEN); | |
1454 | error |= __put_user(0, name->release + __OLD_UTS_LEN); | |
1455 | error |= __copy_to_user(&name->version, &utsname()->version, | |
1456 | __OLD_UTS_LEN); | |
1457 | error |= __put_user(0, name->version + __OLD_UTS_LEN); | |
1458 | error |= __copy_to_user(&name->machine, &utsname()->machine, | |
1459 | __OLD_UTS_LEN); | |
1460 | error |= __put_user(0, name->machine + __OLD_UTS_LEN); | |
1461 | up_read(&uts_sem); | |
1462 | ||
1463 | if (!error && override_architecture(name)) | |
1464 | error = -EFAULT; | |
be27425d AK |
1465 | if (!error && override_release(name->release, sizeof(name->release))) |
1466 | error = -EFAULT; | |
5cacdb4a CH |
1467 | return error ? -EFAULT : 0; |
1468 | } | |
1469 | #endif | |
1470 | ||
5a8a82b1 | 1471 | SYSCALL_DEFINE2(sethostname, char __user *, name, int, len) |
1da177e4 LT |
1472 | { |
1473 | int errno; | |
1474 | char tmp[__NEW_UTS_LEN]; | |
1475 | ||
bb96a6f5 | 1476 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 | 1477 | return -EPERM; |
fc832ad3 | 1478 | |
1da177e4 LT |
1479 | if (len < 0 || len > __NEW_UTS_LEN) |
1480 | return -EINVAL; | |
1481 | down_write(&uts_sem); | |
1482 | errno = -EFAULT; | |
1483 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1484 | struct new_utsname *u = utsname(); |
1485 | ||
1486 | memcpy(u->nodename, tmp, len); | |
1487 | memset(u->nodename + len, 0, sizeof(u->nodename) - len); | |
1da177e4 | 1488 | errno = 0; |
499eea6b | 1489 | uts_proc_notify(UTS_PROC_HOSTNAME); |
1da177e4 LT |
1490 | } |
1491 | up_write(&uts_sem); | |
1492 | return errno; | |
1493 | } | |
1494 | ||
1495 | #ifdef __ARCH_WANT_SYS_GETHOSTNAME | |
1496 | ||
5a8a82b1 | 1497 | SYSCALL_DEFINE2(gethostname, char __user *, name, int, len) |
1da177e4 LT |
1498 | { |
1499 | int i, errno; | |
9679e4dd | 1500 | struct new_utsname *u; |
1da177e4 LT |
1501 | |
1502 | if (len < 0) | |
1503 | return -EINVAL; | |
1504 | down_read(&uts_sem); | |
9679e4dd AM |
1505 | u = utsname(); |
1506 | i = 1 + strlen(u->nodename); | |
1da177e4 LT |
1507 | if (i > len) |
1508 | i = len; | |
1509 | errno = 0; | |
9679e4dd | 1510 | if (copy_to_user(name, u->nodename, i)) |
1da177e4 LT |
1511 | errno = -EFAULT; |
1512 | up_read(&uts_sem); | |
1513 | return errno; | |
1514 | } | |
1515 | ||
1516 | #endif | |
1517 | ||
1518 | /* | |
1519 | * Only setdomainname; getdomainname can be implemented by calling | |
1520 | * uname() | |
1521 | */ | |
5a8a82b1 | 1522 | SYSCALL_DEFINE2(setdomainname, char __user *, name, int, len) |
1da177e4 LT |
1523 | { |
1524 | int errno; | |
1525 | char tmp[__NEW_UTS_LEN]; | |
1526 | ||
fc832ad3 | 1527 | if (!ns_capable(current->nsproxy->uts_ns->user_ns, CAP_SYS_ADMIN)) |
1da177e4 LT |
1528 | return -EPERM; |
1529 | if (len < 0 || len > __NEW_UTS_LEN) | |
1530 | return -EINVAL; | |
1531 | ||
1532 | down_write(&uts_sem); | |
1533 | errno = -EFAULT; | |
1534 | if (!copy_from_user(tmp, name, len)) { | |
9679e4dd AM |
1535 | struct new_utsname *u = utsname(); |
1536 | ||
1537 | memcpy(u->domainname, tmp, len); | |
1538 | memset(u->domainname + len, 0, sizeof(u->domainname) - len); | |
1da177e4 | 1539 | errno = 0; |
499eea6b | 1540 | uts_proc_notify(UTS_PROC_DOMAINNAME); |
1da177e4 LT |
1541 | } |
1542 | up_write(&uts_sem); | |
1543 | return errno; | |
1544 | } | |
1545 | ||
e48fbb69 | 1546 | SYSCALL_DEFINE2(getrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1da177e4 | 1547 | { |
b9518345 JS |
1548 | struct rlimit value; |
1549 | int ret; | |
1550 | ||
1551 | ret = do_prlimit(current, resource, NULL, &value); | |
1552 | if (!ret) | |
1553 | ret = copy_to_user(rlim, &value, sizeof(*rlim)) ? -EFAULT : 0; | |
1554 | ||
1555 | return ret; | |
1da177e4 LT |
1556 | } |
1557 | ||
1558 | #ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT | |
1559 | ||
1560 | /* | |
1561 | * Back compatibility for getrlimit. Needed for some apps. | |
1562 | */ | |
1563 | ||
e48fbb69 HC |
1564 | SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, |
1565 | struct rlimit __user *, rlim) | |
1da177e4 LT |
1566 | { |
1567 | struct rlimit x; | |
1568 | if (resource >= RLIM_NLIMITS) | |
1569 | return -EINVAL; | |
1570 | ||
1571 | task_lock(current->group_leader); | |
1572 | x = current->signal->rlim[resource]; | |
1573 | task_unlock(current->group_leader); | |
756184b7 | 1574 | if (x.rlim_cur > 0x7FFFFFFF) |
1da177e4 | 1575 | x.rlim_cur = 0x7FFFFFFF; |
756184b7 | 1576 | if (x.rlim_max > 0x7FFFFFFF) |
1da177e4 LT |
1577 | x.rlim_max = 0x7FFFFFFF; |
1578 | return copy_to_user(rlim, &x, sizeof(x))?-EFAULT:0; | |
1579 | } | |
1580 | ||
1581 | #endif | |
1582 | ||
c022a0ac JS |
1583 | static inline bool rlim64_is_infinity(__u64 rlim64) |
1584 | { | |
1585 | #if BITS_PER_LONG < 64 | |
1586 | return rlim64 >= ULONG_MAX; | |
1587 | #else | |
1588 | return rlim64 == RLIM64_INFINITY; | |
1589 | #endif | |
1590 | } | |
1591 | ||
1592 | static void rlim_to_rlim64(const struct rlimit *rlim, struct rlimit64 *rlim64) | |
1593 | { | |
1594 | if (rlim->rlim_cur == RLIM_INFINITY) | |
1595 | rlim64->rlim_cur = RLIM64_INFINITY; | |
1596 | else | |
1597 | rlim64->rlim_cur = rlim->rlim_cur; | |
1598 | if (rlim->rlim_max == RLIM_INFINITY) | |
1599 | rlim64->rlim_max = RLIM64_INFINITY; | |
1600 | else | |
1601 | rlim64->rlim_max = rlim->rlim_max; | |
1602 | } | |
1603 | ||
1604 | static void rlim64_to_rlim(const struct rlimit64 *rlim64, struct rlimit *rlim) | |
1605 | { | |
1606 | if (rlim64_is_infinity(rlim64->rlim_cur)) | |
1607 | rlim->rlim_cur = RLIM_INFINITY; | |
1608 | else | |
1609 | rlim->rlim_cur = (unsigned long)rlim64->rlim_cur; | |
1610 | if (rlim64_is_infinity(rlim64->rlim_max)) | |
1611 | rlim->rlim_max = RLIM_INFINITY; | |
1612 | else | |
1613 | rlim->rlim_max = (unsigned long)rlim64->rlim_max; | |
1614 | } | |
1615 | ||
1c1e618d | 1616 | /* make sure you are allowed to change @tsk limits before calling this */ |
5b41535a JS |
1617 | int do_prlimit(struct task_struct *tsk, unsigned int resource, |
1618 | struct rlimit *new_rlim, struct rlimit *old_rlim) | |
1da177e4 | 1619 | { |
5b41535a | 1620 | struct rlimit *rlim; |
86f162f4 | 1621 | int retval = 0; |
1da177e4 LT |
1622 | |
1623 | if (resource >= RLIM_NLIMITS) | |
1624 | return -EINVAL; | |
5b41535a JS |
1625 | if (new_rlim) { |
1626 | if (new_rlim->rlim_cur > new_rlim->rlim_max) | |
1627 | return -EINVAL; | |
1628 | if (resource == RLIMIT_NOFILE && | |
1629 | new_rlim->rlim_max > sysctl_nr_open) | |
1630 | return -EPERM; | |
1631 | } | |
1da177e4 | 1632 | |
1c1e618d JS |
1633 | /* protect tsk->signal and tsk->sighand from disappearing */ |
1634 | read_lock(&tasklist_lock); | |
1635 | if (!tsk->sighand) { | |
1636 | retval = -ESRCH; | |
1637 | goto out; | |
1638 | } | |
1639 | ||
5b41535a | 1640 | rlim = tsk->signal->rlim + resource; |
86f162f4 | 1641 | task_lock(tsk->group_leader); |
5b41535a | 1642 | if (new_rlim) { |
fc832ad3 SH |
1643 | /* Keep the capable check against init_user_ns until |
1644 | cgroups can contain all limits */ | |
5b41535a JS |
1645 | if (new_rlim->rlim_max > rlim->rlim_max && |
1646 | !capable(CAP_SYS_RESOURCE)) | |
1647 | retval = -EPERM; | |
1648 | if (!retval) | |
1649 | retval = security_task_setrlimit(tsk->group_leader, | |
1650 | resource, new_rlim); | |
1651 | if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { | |
1652 | /* | |
1653 | * The caller is asking for an immediate RLIMIT_CPU | |
1654 | * expiry. But we use the zero value to mean "it was | |
1655 | * never set". So let's cheat and make it one second | |
1656 | * instead | |
1657 | */ | |
1658 | new_rlim->rlim_cur = 1; | |
1659 | } | |
1660 | } | |
1661 | if (!retval) { | |
1662 | if (old_rlim) | |
1663 | *old_rlim = *rlim; | |
1664 | if (new_rlim) | |
1665 | *rlim = *new_rlim; | |
9926e4c7 | 1666 | } |
7855c35d | 1667 | task_unlock(tsk->group_leader); |
1da177e4 | 1668 | |
d3561f78 AM |
1669 | /* |
1670 | * RLIMIT_CPU handling. Note that the kernel fails to return an error | |
1671 | * code if it rejected the user's attempt to set RLIMIT_CPU. This is a | |
1672 | * very long-standing error, and fixing it now risks breakage of | |
1673 | * applications, so we live with it | |
1674 | */ | |
5b41535a JS |
1675 | if (!retval && new_rlim && resource == RLIMIT_CPU && |
1676 | new_rlim->rlim_cur != RLIM_INFINITY) | |
1677 | update_rlimit_cpu(tsk, new_rlim->rlim_cur); | |
ec9e16ba | 1678 | out: |
1c1e618d | 1679 | read_unlock(&tasklist_lock); |
2fb9d268 | 1680 | return retval; |
1da177e4 LT |
1681 | } |
1682 | ||
c022a0ac JS |
1683 | /* rcu lock must be held */ |
1684 | static int check_prlimit_permission(struct task_struct *task) | |
1685 | { | |
1686 | const struct cred *cred = current_cred(), *tcred; | |
1687 | ||
fc832ad3 SH |
1688 | if (current == task) |
1689 | return 0; | |
c022a0ac | 1690 | |
fc832ad3 | 1691 | tcred = __task_cred(task); |
5af66203 EB |
1692 | if (uid_eq(cred->uid, tcred->euid) && |
1693 | uid_eq(cred->uid, tcred->suid) && | |
1694 | uid_eq(cred->uid, tcred->uid) && | |
1695 | gid_eq(cred->gid, tcred->egid) && | |
1696 | gid_eq(cred->gid, tcred->sgid) && | |
1697 | gid_eq(cred->gid, tcred->gid)) | |
fc832ad3 | 1698 | return 0; |
c4a4d603 | 1699 | if (ns_capable(tcred->user_ns, CAP_SYS_RESOURCE)) |
fc832ad3 SH |
1700 | return 0; |
1701 | ||
1702 | return -EPERM; | |
c022a0ac JS |
1703 | } |
1704 | ||
1705 | SYSCALL_DEFINE4(prlimit64, pid_t, pid, unsigned int, resource, | |
1706 | const struct rlimit64 __user *, new_rlim, | |
1707 | struct rlimit64 __user *, old_rlim) | |
1708 | { | |
1709 | struct rlimit64 old64, new64; | |
1710 | struct rlimit old, new; | |
1711 | struct task_struct *tsk; | |
1712 | int ret; | |
1713 | ||
1714 | if (new_rlim) { | |
1715 | if (copy_from_user(&new64, new_rlim, sizeof(new64))) | |
1716 | return -EFAULT; | |
1717 | rlim64_to_rlim(&new64, &new); | |
1718 | } | |
1719 | ||
1720 | rcu_read_lock(); | |
1721 | tsk = pid ? find_task_by_vpid(pid) : current; | |
1722 | if (!tsk) { | |
1723 | rcu_read_unlock(); | |
1724 | return -ESRCH; | |
1725 | } | |
1726 | ret = check_prlimit_permission(tsk); | |
1727 | if (ret) { | |
1728 | rcu_read_unlock(); | |
1729 | return ret; | |
1730 | } | |
1731 | get_task_struct(tsk); | |
1732 | rcu_read_unlock(); | |
1733 | ||
1734 | ret = do_prlimit(tsk, resource, new_rlim ? &new : NULL, | |
1735 | old_rlim ? &old : NULL); | |
1736 | ||
1737 | if (!ret && old_rlim) { | |
1738 | rlim_to_rlim64(&old, &old64); | |
1739 | if (copy_to_user(old_rlim, &old64, sizeof(old64))) | |
1740 | ret = -EFAULT; | |
1741 | } | |
1742 | ||
1743 | put_task_struct(tsk); | |
1744 | return ret; | |
1745 | } | |
1746 | ||
7855c35d JS |
1747 | SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) |
1748 | { | |
1749 | struct rlimit new_rlim; | |
1750 | ||
1751 | if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) | |
1752 | return -EFAULT; | |
5b41535a | 1753 | return do_prlimit(current, resource, &new_rlim, NULL); |
7855c35d JS |
1754 | } |
1755 | ||
1da177e4 LT |
1756 | /* |
1757 | * It would make sense to put struct rusage in the task_struct, | |
1758 | * except that would make the task_struct be *really big*. After | |
1759 | * task_struct gets moved into malloc'ed memory, it would | |
1760 | * make sense to do this. It will make moving the rest of the information | |
1761 | * a lot simpler! (Which we're not doing right now because we're not | |
1762 | * measuring them yet). | |
1763 | * | |
1da177e4 LT |
1764 | * When sampling multiple threads for RUSAGE_SELF, under SMP we might have |
1765 | * races with threads incrementing their own counters. But since word | |
1766 | * reads are atomic, we either get new values or old values and we don't | |
1767 | * care which for the sums. We always take the siglock to protect reading | |
1768 | * the c* fields from p->signal from races with exit.c updating those | |
1769 | * fields when reaping, so a sample either gets all the additions of a | |
1770 | * given child after it's reaped, or none so this sample is before reaping. | |
2dd0ebcd | 1771 | * |
de047c1b RT |
1772 | * Locking: |
1773 | * We need to take the siglock for CHILDEREN, SELF and BOTH | |
1774 | * for the cases current multithreaded, non-current single threaded | |
1775 | * non-current multithreaded. Thread traversal is now safe with | |
1776 | * the siglock held. | |
1777 | * Strictly speaking, we donot need to take the siglock if we are current and | |
1778 | * single threaded, as no one else can take our signal_struct away, no one | |
1779 | * else can reap the children to update signal->c* counters, and no one else | |
1780 | * can race with the signal-> fields. If we do not take any lock, the | |
1781 | * signal-> fields could be read out of order while another thread was just | |
1782 | * exiting. So we should place a read memory barrier when we avoid the lock. | |
1783 | * On the writer side, write memory barrier is implied in __exit_signal | |
1784 | * as __exit_signal releases the siglock spinlock after updating the signal-> | |
1785 | * fields. But we don't do this yet to keep things simple. | |
2dd0ebcd | 1786 | * |
1da177e4 LT |
1787 | */ |
1788 | ||
f06febc9 | 1789 | static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r) |
679c9cd4 | 1790 | { |
679c9cd4 SK |
1791 | r->ru_nvcsw += t->nvcsw; |
1792 | r->ru_nivcsw += t->nivcsw; | |
1793 | r->ru_minflt += t->min_flt; | |
1794 | r->ru_majflt += t->maj_flt; | |
1795 | r->ru_inblock += task_io_get_inblock(t); | |
1796 | r->ru_oublock += task_io_get_oublock(t); | |
1797 | } | |
1798 | ||
1da177e4 LT |
1799 | static void k_getrusage(struct task_struct *p, int who, struct rusage *r) |
1800 | { | |
1801 | struct task_struct *t; | |
1802 | unsigned long flags; | |
0cf55e1e | 1803 | cputime_t tgutime, tgstime, utime, stime; |
1f10206c | 1804 | unsigned long maxrss = 0; |
1da177e4 LT |
1805 | |
1806 | memset((char *) r, 0, sizeof *r); | |
64861634 | 1807 | utime = stime = 0; |
1da177e4 | 1808 | |
679c9cd4 | 1809 | if (who == RUSAGE_THREAD) { |
e80d0a1a | 1810 | task_cputime_adjusted(current, &utime, &stime); |
f06febc9 | 1811 | accumulate_thread_rusage(p, r); |
1f10206c | 1812 | maxrss = p->signal->maxrss; |
679c9cd4 SK |
1813 | goto out; |
1814 | } | |
1815 | ||
d6cf723a | 1816 | if (!lock_task_sighand(p, &flags)) |
de047c1b | 1817 | return; |
0f59cc4a | 1818 | |
1da177e4 | 1819 | switch (who) { |
0f59cc4a | 1820 | case RUSAGE_BOTH: |
1da177e4 | 1821 | case RUSAGE_CHILDREN: |
1da177e4 LT |
1822 | utime = p->signal->cutime; |
1823 | stime = p->signal->cstime; | |
1824 | r->ru_nvcsw = p->signal->cnvcsw; | |
1825 | r->ru_nivcsw = p->signal->cnivcsw; | |
1826 | r->ru_minflt = p->signal->cmin_flt; | |
1827 | r->ru_majflt = p->signal->cmaj_flt; | |
6eaeeaba ED |
1828 | r->ru_inblock = p->signal->cinblock; |
1829 | r->ru_oublock = p->signal->coublock; | |
1f10206c | 1830 | maxrss = p->signal->cmaxrss; |
0f59cc4a ON |
1831 | |
1832 | if (who == RUSAGE_CHILDREN) | |
1833 | break; | |
1834 | ||
1da177e4 | 1835 | case RUSAGE_SELF: |
e80d0a1a | 1836 | thread_group_cputime_adjusted(p, &tgutime, &tgstime); |
64861634 MS |
1837 | utime += tgutime; |
1838 | stime += tgstime; | |
1da177e4 LT |
1839 | r->ru_nvcsw += p->signal->nvcsw; |
1840 | r->ru_nivcsw += p->signal->nivcsw; | |
1841 | r->ru_minflt += p->signal->min_flt; | |
1842 | r->ru_majflt += p->signal->maj_flt; | |
6eaeeaba ED |
1843 | r->ru_inblock += p->signal->inblock; |
1844 | r->ru_oublock += p->signal->oublock; | |
1f10206c JP |
1845 | if (maxrss < p->signal->maxrss) |
1846 | maxrss = p->signal->maxrss; | |
1da177e4 LT |
1847 | t = p; |
1848 | do { | |
f06febc9 | 1849 | accumulate_thread_rusage(t, r); |
1da177e4 LT |
1850 | t = next_thread(t); |
1851 | } while (t != p); | |
1da177e4 | 1852 | break; |
0f59cc4a | 1853 | |
1da177e4 LT |
1854 | default: |
1855 | BUG(); | |
1856 | } | |
de047c1b | 1857 | unlock_task_sighand(p, &flags); |
de047c1b | 1858 | |
679c9cd4 | 1859 | out: |
0f59cc4a ON |
1860 | cputime_to_timeval(utime, &r->ru_utime); |
1861 | cputime_to_timeval(stime, &r->ru_stime); | |
1f10206c JP |
1862 | |
1863 | if (who != RUSAGE_CHILDREN) { | |
1864 | struct mm_struct *mm = get_task_mm(p); | |
1865 | if (mm) { | |
1866 | setmax_mm_hiwater_rss(&maxrss, mm); | |
1867 | mmput(mm); | |
1868 | } | |
1869 | } | |
1870 | r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ | |
1da177e4 LT |
1871 | } |
1872 | ||
1873 | int getrusage(struct task_struct *p, int who, struct rusage __user *ru) | |
1874 | { | |
1875 | struct rusage r; | |
1da177e4 | 1876 | k_getrusage(p, who, &r); |
1da177e4 LT |
1877 | return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0; |
1878 | } | |
1879 | ||
e48fbb69 | 1880 | SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) |
1da177e4 | 1881 | { |
679c9cd4 SK |
1882 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && |
1883 | who != RUSAGE_THREAD) | |
1da177e4 LT |
1884 | return -EINVAL; |
1885 | return getrusage(current, who, ru); | |
1886 | } | |
1887 | ||
8d2d5c4a AV |
1888 | #ifdef CONFIG_COMPAT |
1889 | COMPAT_SYSCALL_DEFINE2(getrusage, int, who, struct compat_rusage __user *, ru) | |
1890 | { | |
1891 | struct rusage r; | |
1892 | ||
1893 | if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN && | |
1894 | who != RUSAGE_THREAD) | |
1895 | return -EINVAL; | |
1896 | ||
1897 | k_getrusage(current, who, &r); | |
1898 | return put_compat_rusage(&r, ru); | |
1899 | } | |
1900 | #endif | |
1901 | ||
e48fbb69 | 1902 | SYSCALL_DEFINE1(umask, int, mask) |
1da177e4 LT |
1903 | { |
1904 | mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); | |
1905 | return mask; | |
1906 | } | |
3b7391de | 1907 | |
b32dfe37 CG |
1908 | static int prctl_set_mm_exe_file(struct mm_struct *mm, unsigned int fd) |
1909 | { | |
2903ff01 | 1910 | struct fd exe; |
496ad9aa | 1911 | struct inode *inode; |
2903ff01 | 1912 | int err; |
b32dfe37 | 1913 | |
2903ff01 AV |
1914 | exe = fdget(fd); |
1915 | if (!exe.file) | |
b32dfe37 CG |
1916 | return -EBADF; |
1917 | ||
496ad9aa | 1918 | inode = file_inode(exe.file); |
b32dfe37 CG |
1919 | |
1920 | /* | |
1921 | * Because the original mm->exe_file points to executable file, make | |
1922 | * sure that this one is executable as well, to avoid breaking an | |
1923 | * overall picture. | |
1924 | */ | |
1925 | err = -EACCES; | |
496ad9aa | 1926 | if (!S_ISREG(inode->i_mode) || |
2903ff01 | 1927 | exe.file->f_path.mnt->mnt_flags & MNT_NOEXEC) |
b32dfe37 CG |
1928 | goto exit; |
1929 | ||
496ad9aa | 1930 | err = inode_permission(inode, MAY_EXEC); |
b32dfe37 CG |
1931 | if (err) |
1932 | goto exit; | |
1933 | ||
bafb282d KK |
1934 | down_write(&mm->mmap_sem); |
1935 | ||
1936 | /* | |
4229fb1d | 1937 | * Forbid mm->exe_file change if old file still mapped. |
bafb282d KK |
1938 | */ |
1939 | err = -EBUSY; | |
4229fb1d KK |
1940 | if (mm->exe_file) { |
1941 | struct vm_area_struct *vma; | |
1942 | ||
1943 | for (vma = mm->mmap; vma; vma = vma->vm_next) | |
1944 | if (vma->vm_file && | |
1945 | path_equal(&vma->vm_file->f_path, | |
1946 | &mm->exe_file->f_path)) | |
1947 | goto exit_unlock; | |
bafb282d KK |
1948 | } |
1949 | ||
b32dfe37 CG |
1950 | /* |
1951 | * The symlink can be changed only once, just to disallow arbitrary | |
1952 | * transitions malicious software might bring in. This means one | |
1953 | * could make a snapshot over all processes running and monitor | |
1954 | * /proc/pid/exe changes to notice unusual activity if needed. | |
1955 | */ | |
bafb282d KK |
1956 | err = -EPERM; |
1957 | if (test_and_set_bit(MMF_EXE_FILE_CHANGED, &mm->flags)) | |
1958 | goto exit_unlock; | |
1959 | ||
4229fb1d | 1960 | err = 0; |
2903ff01 | 1961 | set_mm_exe_file(mm, exe.file); /* this grabs a reference to exe.file */ |
bafb282d | 1962 | exit_unlock: |
b32dfe37 CG |
1963 | up_write(&mm->mmap_sem); |
1964 | ||
1965 | exit: | |
2903ff01 | 1966 | fdput(exe); |
b32dfe37 CG |
1967 | return err; |
1968 | } | |
1969 | ||
028ee4be CG |
1970 | static int prctl_set_mm(int opt, unsigned long addr, |
1971 | unsigned long arg4, unsigned long arg5) | |
1972 | { | |
1973 | unsigned long rlim = rlimit(RLIMIT_DATA); | |
028ee4be | 1974 | struct mm_struct *mm = current->mm; |
fe8c7f5c CG |
1975 | struct vm_area_struct *vma; |
1976 | int error; | |
028ee4be | 1977 | |
fe8c7f5c | 1978 | if (arg5 || (arg4 && opt != PR_SET_MM_AUXV)) |
028ee4be CG |
1979 | return -EINVAL; |
1980 | ||
79f0713d | 1981 | if (!capable(CAP_SYS_RESOURCE)) |
028ee4be CG |
1982 | return -EPERM; |
1983 | ||
b32dfe37 CG |
1984 | if (opt == PR_SET_MM_EXE_FILE) |
1985 | return prctl_set_mm_exe_file(mm, (unsigned int)addr); | |
1986 | ||
1ad75b9e | 1987 | if (addr >= TASK_SIZE || addr < mmap_min_addr) |
028ee4be CG |
1988 | return -EINVAL; |
1989 | ||
fe8c7f5c CG |
1990 | error = -EINVAL; |
1991 | ||
028ee4be CG |
1992 | down_read(&mm->mmap_sem); |
1993 | vma = find_vma(mm, addr); | |
1994 | ||
028ee4be CG |
1995 | switch (opt) { |
1996 | case PR_SET_MM_START_CODE: | |
fe8c7f5c CG |
1997 | mm->start_code = addr; |
1998 | break; | |
028ee4be | 1999 | case PR_SET_MM_END_CODE: |
fe8c7f5c | 2000 | mm->end_code = addr; |
028ee4be | 2001 | break; |
028ee4be | 2002 | case PR_SET_MM_START_DATA: |
fe8c7f5c | 2003 | mm->start_data = addr; |
028ee4be | 2004 | break; |
fe8c7f5c CG |
2005 | case PR_SET_MM_END_DATA: |
2006 | mm->end_data = addr; | |
028ee4be CG |
2007 | break; |
2008 | ||
2009 | case PR_SET_MM_START_BRK: | |
2010 | if (addr <= mm->end_data) | |
2011 | goto out; | |
2012 | ||
2013 | if (rlim < RLIM_INFINITY && | |
2014 | (mm->brk - addr) + | |
2015 | (mm->end_data - mm->start_data) > rlim) | |
2016 | goto out; | |
2017 | ||
2018 | mm->start_brk = addr; | |
2019 | break; | |
2020 | ||
2021 | case PR_SET_MM_BRK: | |
2022 | if (addr <= mm->end_data) | |
2023 | goto out; | |
2024 | ||
2025 | if (rlim < RLIM_INFINITY && | |
2026 | (addr - mm->start_brk) + | |
2027 | (mm->end_data - mm->start_data) > rlim) | |
2028 | goto out; | |
2029 | ||
2030 | mm->brk = addr; | |
2031 | break; | |
2032 | ||
fe8c7f5c CG |
2033 | /* |
2034 | * If command line arguments and environment | |
2035 | * are placed somewhere else on stack, we can | |
2036 | * set them up here, ARG_START/END to setup | |
2037 | * command line argumets and ENV_START/END | |
2038 | * for environment. | |
2039 | */ | |
2040 | case PR_SET_MM_START_STACK: | |
2041 | case PR_SET_MM_ARG_START: | |
2042 | case PR_SET_MM_ARG_END: | |
2043 | case PR_SET_MM_ENV_START: | |
2044 | case PR_SET_MM_ENV_END: | |
2045 | if (!vma) { | |
2046 | error = -EFAULT; | |
2047 | goto out; | |
2048 | } | |
fe8c7f5c CG |
2049 | if (opt == PR_SET_MM_START_STACK) |
2050 | mm->start_stack = addr; | |
2051 | else if (opt == PR_SET_MM_ARG_START) | |
2052 | mm->arg_start = addr; | |
2053 | else if (opt == PR_SET_MM_ARG_END) | |
2054 | mm->arg_end = addr; | |
2055 | else if (opt == PR_SET_MM_ENV_START) | |
2056 | mm->env_start = addr; | |
2057 | else if (opt == PR_SET_MM_ENV_END) | |
2058 | mm->env_end = addr; | |
2059 | break; | |
2060 | ||
2061 | /* | |
2062 | * This doesn't move auxiliary vector itself | |
2063 | * since it's pinned to mm_struct, but allow | |
2064 | * to fill vector with new values. It's up | |
2065 | * to a caller to provide sane values here | |
2066 | * otherwise user space tools which use this | |
2067 | * vector might be unhappy. | |
2068 | */ | |
2069 | case PR_SET_MM_AUXV: { | |
2070 | unsigned long user_auxv[AT_VECTOR_SIZE]; | |
2071 | ||
2072 | if (arg4 > sizeof(user_auxv)) | |
2073 | goto out; | |
2074 | up_read(&mm->mmap_sem); | |
2075 | ||
2076 | if (copy_from_user(user_auxv, (const void __user *)addr, arg4)) | |
2077 | return -EFAULT; | |
2078 | ||
2079 | /* Make sure the last entry is always AT_NULL */ | |
2080 | user_auxv[AT_VECTOR_SIZE - 2] = 0; | |
2081 | user_auxv[AT_VECTOR_SIZE - 1] = 0; | |
2082 | ||
2083 | BUILD_BUG_ON(sizeof(user_auxv) != sizeof(mm->saved_auxv)); | |
2084 | ||
2085 | task_lock(current); | |
2086 | memcpy(mm->saved_auxv, user_auxv, arg4); | |
2087 | task_unlock(current); | |
2088 | ||
2089 | return 0; | |
2090 | } | |
028ee4be | 2091 | default: |
028ee4be CG |
2092 | goto out; |
2093 | } | |
2094 | ||
2095 | error = 0; | |
028ee4be CG |
2096 | out: |
2097 | up_read(&mm->mmap_sem); | |
028ee4be CG |
2098 | return error; |
2099 | } | |
300f786b | 2100 | |
52b36941 | 2101 | #ifdef CONFIG_CHECKPOINT_RESTORE |
300f786b CG |
2102 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2103 | { | |
2104 | return put_user(me->clear_child_tid, tid_addr); | |
2105 | } | |
52b36941 | 2106 | #else |
300f786b CG |
2107 | static int prctl_get_tid_address(struct task_struct *me, int __user **tid_addr) |
2108 | { | |
2109 | return -EINVAL; | |
2110 | } | |
028ee4be CG |
2111 | #endif |
2112 | ||
6fa3eb70 S |
2113 | #ifdef CONFIG_MMU |
2114 | static int prctl_update_vma_anon_name(struct vm_area_struct *vma, | |
2115 | struct vm_area_struct **prev, | |
2116 | unsigned long start, unsigned long end, | |
2117 | const char __user *name_addr) | |
2118 | { | |
2119 | struct mm_struct * mm = vma->vm_mm; | |
2120 | int error = 0; | |
2121 | pgoff_t pgoff; | |
2122 | ||
2123 | if (name_addr == vma_get_anon_name(vma)) { | |
2124 | *prev = vma; | |
2125 | goto out; | |
2126 | } | |
2127 | ||
2128 | pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT); | |
2129 | *prev = vma_merge(mm, *prev, start, end, vma->vm_flags, vma->anon_vma, | |
2130 | vma->vm_file, pgoff, vma_policy(vma), | |
2131 | name_addr); | |
2132 | if (*prev) { | |
2133 | vma = *prev; | |
2134 | goto success; | |
2135 | } | |
2136 | ||
2137 | *prev = vma; | |
2138 | ||
2139 | if (start != vma->vm_start) { | |
2140 | error = split_vma(mm, vma, start, 1); | |
2141 | if (error) | |
2142 | goto out; | |
2143 | } | |
2144 | ||
2145 | if (end != vma->vm_end) { | |
2146 | error = split_vma(mm, vma, end, 0); | |
2147 | if (error) | |
2148 | goto out; | |
2149 | } | |
2150 | ||
2151 | success: | |
2152 | if (!vma->vm_file) | |
2153 | vma->shared.anon_name = name_addr; | |
2154 | ||
2155 | out: | |
2156 | if (error == -ENOMEM) | |
2157 | error = -EAGAIN; | |
2158 | return error; | |
2159 | } | |
2160 | ||
2161 | static int prctl_set_vma_anon_name(unsigned long start, unsigned long end, | |
2162 | unsigned long arg) | |
2163 | { | |
2164 | unsigned long tmp; | |
2165 | struct vm_area_struct * vma, *prev; | |
2166 | int unmapped_error = 0; | |
2167 | int error = -EINVAL; | |
2168 | ||
2169 | /* | |
2170 | * If the interval [start,end) covers some unmapped address | |
2171 | * ranges, just ignore them, but return -ENOMEM at the end. | |
2172 | * - this matches the handling in madvise. | |
2173 | */ | |
2174 | vma = find_vma_prev(current->mm, start, &prev); | |
2175 | if (vma && start > vma->vm_start) | |
2176 | prev = vma; | |
2177 | ||
2178 | for (;;) { | |
2179 | /* Still start < end. */ | |
2180 | error = -ENOMEM; | |
2181 | if (!vma) | |
2182 | return error; | |
2183 | ||
2184 | /* Here start < (end|vma->vm_end). */ | |
2185 | if (start < vma->vm_start) { | |
2186 | unmapped_error = -ENOMEM; | |
2187 | start = vma->vm_start; | |
2188 | if (start >= end) | |
2189 | return error; | |
2190 | } | |
2191 | ||
2192 | /* Here vma->vm_start <= start < (end|vma->vm_end) */ | |
2193 | tmp = vma->vm_end; | |
2194 | if (end < tmp) | |
2195 | tmp = end; | |
2196 | ||
2197 | /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */ | |
2198 | error = prctl_update_vma_anon_name(vma, &prev, start, tmp, | |
2199 | (const char __user *)arg); | |
2200 | if (error) | |
2201 | return error; | |
2202 | start = tmp; | |
2203 | if (prev && start < prev->vm_end) | |
2204 | start = prev->vm_end; | |
2205 | error = unmapped_error; | |
2206 | if (start >= end) | |
2207 | return error; | |
2208 | if (prev) | |
2209 | vma = prev->vm_next; | |
2210 | else /* madvise_remove dropped mmap_sem */ | |
2211 | vma = find_vma(current->mm, start); | |
2212 | } | |
2213 | } | |
2214 | ||
2215 | static int prctl_set_vma(unsigned long opt, unsigned long start, | |
2216 | unsigned long len_in, unsigned long arg) | |
2217 | { | |
2218 | struct mm_struct *mm = current->mm; | |
2219 | int error; | |
2220 | unsigned long len; | |
2221 | unsigned long end; | |
2222 | ||
2223 | #ifndef CONFIG_MT_ENG_BUILD | |
2224 | /* Do not do prctl_set_vma in !eng load */ | |
2225 | return 0; | |
2226 | #endif | |
2227 | ||
2228 | if (start & ~PAGE_MASK) | |
2229 | return -EINVAL; | |
2230 | len = (len_in + ~PAGE_MASK) & PAGE_MASK; | |
2231 | ||
2232 | /* Check to see whether len was rounded up from small -ve to zero */ | |
2233 | if (len_in && !len) | |
2234 | return -EINVAL; | |
2235 | ||
2236 | end = start + len; | |
2237 | if (end < start) | |
2238 | return -EINVAL; | |
2239 | ||
2240 | if (end == start) | |
2241 | return 0; | |
2242 | ||
2243 | down_write(&mm->mmap_sem); | |
2244 | ||
2245 | switch (opt) { | |
2246 | case PR_SET_VMA_ANON_NAME: | |
2247 | error = prctl_set_vma_anon_name(start, end, arg); | |
2248 | break; | |
2249 | default: | |
2250 | error = -EINVAL; | |
2251 | } | |
2252 | ||
2253 | up_write(&mm->mmap_sem); | |
2254 | ||
2255 | return error; | |
2256 | } | |
2257 | #else /* CONFIG_MMU */ | |
2258 | static int prctl_set_vma(unsigned long opt, unsigned long start, | |
2259 | unsigned long len_in, unsigned long arg) | |
2260 | { | |
2261 | return -EINVAL; | |
2262 | } | |
2263 | #endif | |
2264 | ||
c4ea37c2 HC |
2265 | SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, |
2266 | unsigned long, arg4, unsigned long, arg5) | |
1da177e4 | 2267 | { |
b6dff3ec | 2268 | struct task_struct *me = current; |
6fa3eb70 | 2269 | struct task_struct *tsk; |
b6dff3ec DH |
2270 | unsigned char comm[sizeof(me->comm)]; |
2271 | long error; | |
1da177e4 | 2272 | |
d84f4f99 DH |
2273 | error = security_task_prctl(option, arg2, arg3, arg4, arg5); |
2274 | if (error != -ENOSYS) | |
1da177e4 LT |
2275 | return error; |
2276 | ||
d84f4f99 | 2277 | error = 0; |
1da177e4 | 2278 | switch (option) { |
f3cbd435 AM |
2279 | case PR_SET_PDEATHSIG: |
2280 | if (!valid_signal(arg2)) { | |
2281 | error = -EINVAL; | |
1da177e4 | 2282 | break; |
f3cbd435 AM |
2283 | } |
2284 | me->pdeath_signal = arg2; | |
2285 | break; | |
2286 | case PR_GET_PDEATHSIG: | |
2287 | error = put_user(me->pdeath_signal, (int __user *)arg2); | |
2288 | break; | |
2289 | case PR_GET_DUMPABLE: | |
2290 | error = get_dumpable(me->mm); | |
2291 | break; | |
2292 | case PR_SET_DUMPABLE: | |
2293 | if (arg2 != SUID_DUMP_DISABLE && arg2 != SUID_DUMP_USER) { | |
2294 | error = -EINVAL; | |
1da177e4 | 2295 | break; |
f3cbd435 AM |
2296 | } |
2297 | set_dumpable(me->mm, arg2); | |
2298 | break; | |
1da177e4 | 2299 | |
f3cbd435 AM |
2300 | case PR_SET_UNALIGN: |
2301 | error = SET_UNALIGN_CTL(me, arg2); | |
2302 | break; | |
2303 | case PR_GET_UNALIGN: | |
2304 | error = GET_UNALIGN_CTL(me, arg2); | |
2305 | break; | |
2306 | case PR_SET_FPEMU: | |
2307 | error = SET_FPEMU_CTL(me, arg2); | |
2308 | break; | |
2309 | case PR_GET_FPEMU: | |
2310 | error = GET_FPEMU_CTL(me, arg2); | |
2311 | break; | |
2312 | case PR_SET_FPEXC: | |
2313 | error = SET_FPEXC_CTL(me, arg2); | |
2314 | break; | |
2315 | case PR_GET_FPEXC: | |
2316 | error = GET_FPEXC_CTL(me, arg2); | |
2317 | break; | |
2318 | case PR_GET_TIMING: | |
2319 | error = PR_TIMING_STATISTICAL; | |
2320 | break; | |
2321 | case PR_SET_TIMING: | |
2322 | if (arg2 != PR_TIMING_STATISTICAL) | |
2323 | error = -EINVAL; | |
2324 | break; | |
2325 | case PR_SET_NAME: | |
2326 | comm[sizeof(me->comm) - 1] = 0; | |
2327 | if (strncpy_from_user(comm, (char __user *)arg2, | |
2328 | sizeof(me->comm) - 1) < 0) | |
2329 | return -EFAULT; | |
2330 | set_task_comm(me, comm); | |
2331 | proc_comm_connector(me); | |
2332 | break; | |
2333 | case PR_GET_NAME: | |
2334 | get_task_comm(comm, me); | |
2335 | if (copy_to_user((char __user *)arg2, comm, sizeof(comm))) | |
2336 | return -EFAULT; | |
2337 | break; | |
2338 | case PR_GET_ENDIAN: | |
2339 | error = GET_ENDIAN(me, arg2); | |
2340 | break; | |
2341 | case PR_SET_ENDIAN: | |
2342 | error = SET_ENDIAN(me, arg2); | |
2343 | break; | |
2344 | case PR_GET_SECCOMP: | |
2345 | error = prctl_get_seccomp(); | |
2346 | break; | |
2347 | case PR_SET_SECCOMP: | |
2348 | error = prctl_set_seccomp(arg2, (char __user *)arg3); | |
2349 | break; | |
2350 | case PR_GET_TSC: | |
2351 | error = GET_TSC_CTL(arg2); | |
2352 | break; | |
2353 | case PR_SET_TSC: | |
2354 | error = SET_TSC_CTL(arg2); | |
2355 | break; | |
2356 | case PR_TASK_PERF_EVENTS_DISABLE: | |
2357 | error = perf_event_task_disable(); | |
2358 | break; | |
2359 | case PR_TASK_PERF_EVENTS_ENABLE: | |
2360 | error = perf_event_task_enable(); | |
2361 | break; | |
2362 | case PR_GET_TIMERSLACK: | |
2363 | error = current->timer_slack_ns; | |
2364 | break; | |
2365 | case PR_SET_TIMERSLACK: | |
2366 | if (arg2 <= 0) | |
2367 | current->timer_slack_ns = | |
6976675d | 2368 | current->default_timer_slack_ns; |
f3cbd435 AM |
2369 | else |
2370 | current->timer_slack_ns = arg2; | |
2371 | break; | |
2372 | case PR_MCE_KILL: | |
2373 | if (arg4 | arg5) | |
2374 | return -EINVAL; | |
2375 | switch (arg2) { | |
2376 | case PR_MCE_KILL_CLEAR: | |
2377 | if (arg3 != 0) | |
4db96cf0 | 2378 | return -EINVAL; |
f3cbd435 | 2379 | current->flags &= ~PF_MCE_PROCESS; |
4db96cf0 | 2380 | break; |
f3cbd435 AM |
2381 | case PR_MCE_KILL_SET: |
2382 | current->flags |= PF_MCE_PROCESS; | |
2383 | if (arg3 == PR_MCE_KILL_EARLY) | |
2384 | current->flags |= PF_MCE_EARLY; | |
2385 | else if (arg3 == PR_MCE_KILL_LATE) | |
2386 | current->flags &= ~PF_MCE_EARLY; | |
2387 | else if (arg3 == PR_MCE_KILL_DEFAULT) | |
2388 | current->flags &= | |
2389 | ~(PF_MCE_EARLY|PF_MCE_PROCESS); | |
1087e9b4 | 2390 | else |
259e5e6c | 2391 | return -EINVAL; |
259e5e6c | 2392 | break; |
6fa3eb70 S |
2393 | case PR_SET_TIMERSLACK_PID: |
2394 | if (current->pid != (pid_t)arg3 && | |
2395 | !capable(CAP_SYS_NICE)) | |
2396 | return -EPERM; | |
2397 | rcu_read_lock(); | |
2398 | tsk = find_task_by_pid_ns((pid_t)arg3, &init_pid_ns); | |
2399 | if (tsk == NULL) { | |
2400 | rcu_read_unlock(); | |
2401 | return -EINVAL; | |
2402 | } | |
2403 | get_task_struct(tsk); | |
2404 | rcu_read_unlock(); | |
2405 | if (arg2 <= 0) | |
2406 | tsk->timer_slack_ns = | |
2407 | tsk->default_timer_slack_ns; | |
2408 | else | |
2409 | tsk->timer_slack_ns = arg2; | |
2410 | put_task_struct(tsk); | |
2411 | error = 0; | |
2412 | break; | |
1da177e4 | 2413 | default: |
f3cbd435 AM |
2414 | return -EINVAL; |
2415 | } | |
2416 | break; | |
2417 | case PR_MCE_KILL_GET: | |
2418 | if (arg2 | arg3 | arg4 | arg5) | |
2419 | return -EINVAL; | |
2420 | if (current->flags & PF_MCE_PROCESS) | |
2421 | error = (current->flags & PF_MCE_EARLY) ? | |
2422 | PR_MCE_KILL_EARLY : PR_MCE_KILL_LATE; | |
2423 | else | |
2424 | error = PR_MCE_KILL_DEFAULT; | |
2425 | break; | |
2426 | case PR_SET_MM: | |
2427 | error = prctl_set_mm(arg2, arg3, arg4, arg5); | |
2428 | break; | |
2429 | case PR_GET_TID_ADDRESS: | |
2430 | error = prctl_get_tid_address(me, (int __user **)arg2); | |
2431 | break; | |
2432 | case PR_SET_CHILD_SUBREAPER: | |
2433 | me->signal->is_child_subreaper = !!arg2; | |
2434 | break; | |
2435 | case PR_GET_CHILD_SUBREAPER: | |
2436 | error = put_user(me->signal->is_child_subreaper, | |
2437 | (int __user *)arg2); | |
2438 | break; | |
2439 | case PR_SET_NO_NEW_PRIVS: | |
2440 | if (arg2 != 1 || arg3 || arg4 || arg5) | |
2441 | return -EINVAL; | |
2442 | ||
6fa3eb70 | 2443 | task_set_no_new_privs(current); |
f3cbd435 AM |
2444 | break; |
2445 | case PR_GET_NO_NEW_PRIVS: | |
2446 | if (arg2 || arg3 || arg4 || arg5) | |
2447 | return -EINVAL; | |
6fa3eb70 S |
2448 | return task_no_new_privs(current) ? 1 : 0; |
2449 | case PR_SET_VMA: | |
2450 | error = prctl_set_vma(arg2, arg3, arg4, arg5); | |
2451 | break; | |
f3cbd435 AM |
2452 | default: |
2453 | error = -EINVAL; | |
2454 | break; | |
1da177e4 LT |
2455 | } |
2456 | return error; | |
2457 | } | |
3cfc348b | 2458 | |
836f92ad HC |
2459 | SYSCALL_DEFINE3(getcpu, unsigned __user *, cpup, unsigned __user *, nodep, |
2460 | struct getcpu_cache __user *, unused) | |
3cfc348b AK |
2461 | { |
2462 | int err = 0; | |
2463 | int cpu = raw_smp_processor_id(); | |
2464 | if (cpup) | |
2465 | err |= put_user(cpu, cpup); | |
2466 | if (nodep) | |
2467 | err |= put_user(cpu_to_node(cpu), nodep); | |
3cfc348b AK |
2468 | return err ? -EFAULT : 0; |
2469 | } | |
10a0a8d4 JF |
2470 | |
2471 | char poweroff_cmd[POWEROFF_CMD_PATH_LEN] = "/sbin/poweroff"; | |
2472 | ||
2ca067ef | 2473 | static int __orderly_poweroff(bool force) |
10a0a8d4 | 2474 | { |
b57b44ae | 2475 | char **argv; |
10a0a8d4 JF |
2476 | static char *envp[] = { |
2477 | "HOME=/", | |
2478 | "PATH=/sbin:/bin:/usr/sbin:/usr/bin", | |
2479 | NULL | |
2480 | }; | |
b57b44ae | 2481 | int ret; |
10a0a8d4 | 2482 | |
2ca067ef ON |
2483 | argv = argv_split(GFP_KERNEL, poweroff_cmd, NULL); |
2484 | if (argv) { | |
2485 | ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_EXEC); | |
2486 | argv_free(argv); | |
2487 | } else { | |
10a0a8d4 | 2488 | printk(KERN_WARNING "%s failed to allocate memory for \"%s\"\n", |
2ca067ef ON |
2489 | __func__, poweroff_cmd); |
2490 | ret = -ENOMEM; | |
10a0a8d4 JF |
2491 | } |
2492 | ||
2ca067ef ON |
2493 | if (ret && force) { |
2494 | printk(KERN_WARNING "Failed to start orderly shutdown: " | |
2495 | "forcing the issue\n"); | |
2496 | /* | |
2497 | * I guess this should try to kick off some daemon to sync and | |
2498 | * poweroff asap. Or not even bother syncing if we're doing an | |
2499 | * emergency shutdown? | |
2500 | */ | |
2501 | emergency_sync(); | |
2502 | kernel_power_off(); | |
2503 | } | |
10a0a8d4 | 2504 | |
b57b44ae AM |
2505 | return ret; |
2506 | } | |
2507 | ||
2ca067ef ON |
2508 | static bool poweroff_force; |
2509 | ||
2510 | static void poweroff_work_func(struct work_struct *work) | |
2511 | { | |
2512 | __orderly_poweroff(poweroff_force); | |
2513 | } | |
2514 | ||
2515 | static DECLARE_WORK(poweroff_work, poweroff_work_func); | |
2516 | ||
b57b44ae AM |
2517 | /** |
2518 | * orderly_poweroff - Trigger an orderly system poweroff | |
2519 | * @force: force poweroff if command execution fails | |
2520 | * | |
2521 | * This may be called from any context to trigger a system shutdown. | |
2522 | * If the orderly shutdown fails, it will force an immediate shutdown. | |
2523 | */ | |
2524 | int orderly_poweroff(bool force) | |
2525 | { | |
2ca067ef ON |
2526 | if (force) /* do not override the pending "true" */ |
2527 | poweroff_force = true; | |
2528 | schedule_work(&poweroff_work); | |
2529 | return 0; | |
10a0a8d4 JF |
2530 | } |
2531 | EXPORT_SYMBOL_GPL(orderly_poweroff); | |
4a22f166 SR |
2532 | |
2533 | /** | |
2534 | * do_sysinfo - fill in sysinfo struct | |
2535 | * @info: pointer to buffer to fill | |
2536 | */ | |
2537 | static int do_sysinfo(struct sysinfo *info) | |
2538 | { | |
2539 | unsigned long mem_total, sav_total; | |
2540 | unsigned int mem_unit, bitcount; | |
2541 | struct timespec tp; | |
2542 | ||
2543 | memset(info, 0, sizeof(struct sysinfo)); | |
2544 | ||
2545 | ktime_get_ts(&tp); | |
2546 | monotonic_to_bootbased(&tp); | |
2547 | info->uptime = tp.tv_sec + (tp.tv_nsec ? 1 : 0); | |
2548 | ||
2549 | get_avenrun(info->loads, 0, SI_LOAD_SHIFT - FSHIFT); | |
2550 | ||
2551 | info->procs = nr_threads; | |
2552 | ||
2553 | si_meminfo(info); | |
2554 | si_swapinfo(info); | |
2555 | ||
2556 | /* | |
2557 | * If the sum of all the available memory (i.e. ram + swap) | |
2558 | * is less than can be stored in a 32 bit unsigned long then | |
2559 | * we can be binary compatible with 2.2.x kernels. If not, | |
2560 | * well, in that case 2.2.x was broken anyways... | |
2561 | * | |
2562 | * -Erik Andersen <andersee@debian.org> | |
2563 | */ | |
2564 | ||
2565 | mem_total = info->totalram + info->totalswap; | |
2566 | if (mem_total < info->totalram || mem_total < info->totalswap) | |
2567 | goto out; | |
2568 | bitcount = 0; | |
2569 | mem_unit = info->mem_unit; | |
2570 | while (mem_unit > 1) { | |
2571 | bitcount++; | |
2572 | mem_unit >>= 1; | |
2573 | sav_total = mem_total; | |
2574 | mem_total <<= 1; | |
2575 | if (mem_total < sav_total) | |
2576 | goto out; | |
2577 | } | |
2578 | ||
2579 | /* | |
2580 | * If mem_total did not overflow, multiply all memory values by | |
2581 | * info->mem_unit and set it to 1. This leaves things compatible | |
2582 | * with 2.2.x, and also retains compatibility with earlier 2.4.x | |
2583 | * kernels... | |
2584 | */ | |
2585 | ||
2586 | info->mem_unit = 1; | |
2587 | info->totalram <<= bitcount; | |
2588 | info->freeram <<= bitcount; | |
2589 | info->sharedram <<= bitcount; | |
2590 | info->bufferram <<= bitcount; | |
2591 | info->totalswap <<= bitcount; | |
2592 | info->freeswap <<= bitcount; | |
2593 | info->totalhigh <<= bitcount; | |
2594 | info->freehigh <<= bitcount; | |
2595 | ||
2596 | out: | |
2597 | return 0; | |
2598 | } | |
2599 | ||
2600 | SYSCALL_DEFINE1(sysinfo, struct sysinfo __user *, info) | |
2601 | { | |
2602 | struct sysinfo val; | |
2603 | ||
2604 | do_sysinfo(&val); | |
2605 | ||
2606 | if (copy_to_user(info, &val, sizeof(struct sysinfo))) | |
2607 | return -EFAULT; | |
2608 | ||
2609 | return 0; | |
2610 | } | |
2611 | ||
2612 | #ifdef CONFIG_COMPAT | |
2613 | struct compat_sysinfo { | |
2614 | s32 uptime; | |
2615 | u32 loads[3]; | |
2616 | u32 totalram; | |
2617 | u32 freeram; | |
2618 | u32 sharedram; | |
2619 | u32 bufferram; | |
2620 | u32 totalswap; | |
2621 | u32 freeswap; | |
2622 | u16 procs; | |
2623 | u16 pad; | |
2624 | u32 totalhigh; | |
2625 | u32 freehigh; | |
2626 | u32 mem_unit; | |
2627 | char _f[20-2*sizeof(u32)-sizeof(int)]; | |
2628 | }; | |
2629 | ||
2630 | COMPAT_SYSCALL_DEFINE1(sysinfo, struct compat_sysinfo __user *, info) | |
2631 | { | |
2632 | struct sysinfo s; | |
2633 | ||
2634 | do_sysinfo(&s); | |
2635 | ||
2636 | /* Check to see if any memory value is too large for 32-bit and scale | |
2637 | * down if needed | |
2638 | */ | |
2639 | if ((s.totalram >> 32) || (s.totalswap >> 32)) { | |
2640 | int bitcount = 0; | |
2641 | ||
2642 | while (s.mem_unit < PAGE_SIZE) { | |
2643 | s.mem_unit <<= 1; | |
2644 | bitcount++; | |
2645 | } | |
2646 | ||
2647 | s.totalram >>= bitcount; | |
2648 | s.freeram >>= bitcount; | |
2649 | s.sharedram >>= bitcount; | |
2650 | s.bufferram >>= bitcount; | |
2651 | s.totalswap >>= bitcount; | |
2652 | s.freeswap >>= bitcount; | |
2653 | s.totalhigh >>= bitcount; | |
2654 | s.freehigh >>= bitcount; | |
2655 | } | |
2656 | ||
2657 | if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) || | |
2658 | __put_user(s.uptime, &info->uptime) || | |
2659 | __put_user(s.loads[0], &info->loads[0]) || | |
2660 | __put_user(s.loads[1], &info->loads[1]) || | |
2661 | __put_user(s.loads[2], &info->loads[2]) || | |
2662 | __put_user(s.totalram, &info->totalram) || | |
2663 | __put_user(s.freeram, &info->freeram) || | |
2664 | __put_user(s.sharedram, &info->sharedram) || | |
2665 | __put_user(s.bufferram, &info->bufferram) || | |
2666 | __put_user(s.totalswap, &info->totalswap) || | |
2667 | __put_user(s.freeswap, &info->freeswap) || | |
2668 | __put_user(s.procs, &info->procs) || | |
2669 | __put_user(s.totalhigh, &info->totalhigh) || | |
2670 | __put_user(s.freehigh, &info->freehigh) || | |
2671 | __put_user(s.mem_unit, &info->mem_unit)) | |
2672 | return -EFAULT; | |
2673 | ||
2674 | return 0; | |
2675 | } | |
2676 | #endif /* CONFIG_COMPAT */ |